The Flickr Cavradi Image Generatr

Quartz-tourmaline from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
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Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Val Aulta, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz-tourmaline from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Val Aulta, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz-tourmaline from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Val Aulta, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz-tourmaline from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Val Aulta, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz gwindel from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Crest Lad", Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz gwindel from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Igl lert", Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz gwindel from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Crest Lad", Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Sur il fuorn grond", Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz gwindel from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Igl lert", Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Sur il fuorn grond", Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystals from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Curnera Dam, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Curnera Dam, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystals from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Curnera Dam, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Curnera Dam, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystals from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
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Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
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Locality: "Val da Cristallas" ravine, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystals from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Val da Cristallas" ravine, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.

The brownish color of the quartz is from inclusions of goethite, FeO(OH) - iron hydroxy-oxide.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Curnera Dam, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.

The brownish color of the quartz is from inclusions of goethite, FeO(OH) - iron hydroxy-oxide.

The small area of rainbow colors is from two-beam interference. Light that passes through transparent or translucent minerals will get partially reflected back to the viewer by internal fractures or cleavage planes. Partial light reflection occurs on both sides of the fracture. The light reflecting from the back side of the fracture will travel slightly farther to the viewer than light reflecting from the front side of the fracture. The two beams of light interfere with each other, resulting in rainbow colors. This phenomenon can be seen in calcite, quartz, fluorite, opal, obsidian, and likely other materials.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: Curnera Dam, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Val Aulta" ravine, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland

Quartz crystal from Switzerland.

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 6100 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.

The silicates are the most abundant and chemically complex group of minerals. All silicates have silica as the basis for their chemistry. "Silica" refers to SiO2 chemistry. The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4. Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens "belong" to each silicon. The resulting formula for silica is thus SiO2, not SiO4.

The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2). All other silicates have silica + impurities. Many silicates have a significant percentage of aluminum (the aluminosilicates).

Quartz (silicon dioxide/silica - SiO2) is the most common mineral in the Earth's crust. It is composed of the two most abundant elements in the crust - oxygen and silicon. It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals (even though it's in the trigonal crystal system), has no cleavage, and has conchoidal fracture. Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.
--------------------------------
Exhibit info.:

Cavradi Gorge is one of Switzerland's premier mineral localities. "Cavradi", a well-illustrated book about the mineralogy of Cavradi written by local experts, was published in 2013. For nearly 200 years, superb hematite and quartz crystals have been won from "alpine clefts" in the ravines on either side of Cavrado Gorge by local professional mineral collectors called "Strahlers". In the book, the ravines are named.
--------------------------------
Locality: "Val Aulta" ravine, Cavradi Gorge, Graubunden, Swiss Alps, Switzerland