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Azurite Pigments
Azurite was ground and used as a pigment in blue paint as early as ancient Egypt. Through time, its use became much more common. During the Middle Ages and Renaissance, it was the most important blue pigment used in Europe. Much of the azurite used to make the pigment was mined in France. Making pigment from…
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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 Crystal Habit?
Crystal habit is the tendency for specimens of a mineral to repeatedly grow into characteristic shapes. These shapes are influenced by the atomic structure of the mineral, but they can also be influenced by the environment of crystal growth. Regardless of influence, crystal habit shapes can be characteristic of the mineral and displayed by many specimens of…
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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…
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Olivine and the Gemstone Peridot
Olivine is also the mineral of the gemstone known as “peridot.” It is a yellow-green to green gemstone that is very popular in jewelry. Peridot serves as a birthstone for the month of August. The most valued colors are dark olive green and a bright lime green. These specimens are of the mineral forsterite because the iron-rich fayalite is…
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Uses of Olivine
Olivine is a mineral that is not often used in industry. Most olivine is used in metallurgical processes as a slag conditioner. High-magnesium olivine (forsterite) is added to blast furnaces to remove impurities from steel and to form a slag. Olivine has also been used as a refractory material. It is used to make refractory…
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Tumbled Stone Crafts and Gifts
Most rock tumbler kits are supplied with a small jewelry kit that you can use to make a couple gift items from your first batch of tumbled stones. Keychains, pendant necklaces and other small jewelry items make great gifts. Tumbled stones can also be used for many other things. They can be used as accents or…
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Your Kids Want a Rock Tumbler?
Nice! Rock tumbling is a great family activity – and that’s the way the hobby should be done. Children under age 14 require adult help and supervision. They will need help following the instructions, help opening tumbler barrels with small hands, and 100% supervision because a rock tumbler has a motor that is powered by…