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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…
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What Types of Rock Can Be Tumbled?
Most rocks will not perform well in a rock tumbler; however, a few types of rock can be successfully tumbled by a beginner if the rocks are carefully selected. These easy-to-tumble rocks include agate, jasper, chalcedony, and petrified wood. All of these materials are composed of microcrystalline quartz, which is a very hard, tough, and…
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COMMERCIAL ROCK TUMBLERS
Commercial tumblers are large machines that can tumble a few dozen to a few thousand pounds of rock at a time. They cost several hundred to many thousands of dollars and are used almost exclusively by people and companies who are in the business of producing tumbled stones.
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HOBBYIST ROCK TUMBLERS
Hobbyist tumblers typically sell for between $70 and $300, depending mainly upon their size. Most are made with a metal frame and a quality motor designed to operate for years. They operate quietly because they have a rubber barrel or a metal barrel lined with rubber. They typically tumble between two and ten pounds of rock.Hobbyist tumblers were first made in the late 1950s. Two brands, Thumler’s Tumblers and Lortone, are still being manufactured today with very little change to their basic design. Successful products persist in the marketplace. Many people received a hobbyist tumbler by Thumler’s or Lortone as a gift when they were a child and are now…
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Types and Sizes of Rotary Tumblers
Rock tumblers are made in a wide range of sizes for different types of use. The three basic categories are described below. TOY ROCK TUMBLERSThe smallest and least expensive tumblers are toy tumblers with a plastic body and barrel. These machines typically sell for between $40 and $80 online or in local toy and craft…
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How Do Rock Tumblers Work?
The most popular tumblers have a barrel that is loaded with rocks, water, and abrasive grit. The abrasive grit is a granular material similar to the grains glued onto sandpaper. The grit is often labeled “coarse,” “medium,” and “fine,” similar to the different grades of sandpaper. The barrel containing rocks, grit, and water is placed…