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Geologic Occurrence of Goshenite
Most gem-quality goshenite crystals form in cavities below Earth’s surface, on the fringes of a granitic magma body in its late stages of crystallization. The cavities provide open space for the uninterrupted growth of crystals. The late-stage timing is when beryllium-rich fluids are exiting the magma body. An abundant supply of beryllium is needed to form goshenite, a variety…
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The Curse of Being Colorless
Unlike emerald and aquamarine, goshenite has not become popular in the jewelry industry. There are two likely reasons for this: 1) goshenite’s lack of color does not attract people like the green of emerald and the blue of aquamarine; and, 2) goshenite does not have a level of brilliance, luster, or fire that enables it to compete as…
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What is Goshenite?
Goshenite, also known as white beryl, is the colorless to near-colorless variety of beryl. It is named after Goshen, Massachusetts, a community near one of the first deposits found in the United States. Goshenite is often found as colorless to near-colorless, hexagonal crystals with exceptional clarity. It is also found as water-worn pebbles in alluvial deposits. Faceted Goshenite: This…
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Physical Properties of Malachite
Malachite’s most striking physical property is its green color. All specimens of the mineral are green and range from a pastel green, to a bright green, to an extremely dark green that is almost black. It is typically found as stalactites and botryoidal coatings on the surfaces of underground cavities – similar to the deposits…
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Where Does Malachite Form?
Malachite is a mineral that forms at shallow depths within the Earth, in the oxidizing zone above copper deposits. It precipitates from descending solutions in fractures, caverns, cavities, and the intergranular spaces of porous rock. It often forms within limestone where a subsurface chemical environment favorable for the formation of carbonate minerals can occur. Associated minerals include azurite, bornite, calcite, chalcopyrite, copper,…
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What is Malachite?
Malachite is a green copper carbonate hydroxide mineral with a chemical composition of Cu2(CO3)(OH)2. It was one of the first ores used to produce copper metal. It is of minor importance today as an ore of copper because it is usually found in small quantities and can be sold for higher prices for other types of use. Malachite has been…
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Uses of Azurite
While azurite is not an extremely abundant mineral and is rarely found in large deposits, it has been used in a number of ways. Some of these are explained below. Copper Prospecting and Mining Geologists know that abundant azurite is often found in the rocks above deposits of copper ore. That enables them to use azurite as…
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Physical Properties of Azurite
The most diagnostic property of azurite is it distinctive deep blue color. It is also soft with a Mohs hardness of only 3.5 to 4. It contains copper, which gives its blue color and a specific gravity of 3.7 to 3.9, which is exceptionally high for a non-metallic mineral. Azurite is a carbonate mineral and produces a…
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Geologic Occurrence
Azurite is a secondary mineral that usually forms when carbon-dioxide-laden waters descend into the Earth and react with subsurface copper ores. The carbonic acid of these waters dissolves small amounts of copper from the ore. The dissolved copper is transported with the water until it reaches a new geochemical environment. This new environment could be a location where water…
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What is Azurite?
Azurite is a copper carbonate hydroxide mineral with a chemical composition of Cu3(CO3)2(OH)2. It is best known for its characteristic deep blue to violet-blue color. The blue color, known as “azure,” is like the deep blue evening skies often seen above deserts and winter landscapes. Azurite is not a common or abundant mineral, but it is beautiful…