Mineral Guides

Quick answer: A tumbled stone is made by rotating rough stones in a barrel with water and progressively finer abrasive

Quick answer: Apatite is a calcium phosphate mineral, and one form of it, hydroxyapatite, is the main mineral in human

Quick answer: A cabochon is a gem cut with a smooth, domed top and usually a flat back, instead of

Quick answer: Mica’s flat, flexible, heat-proof sheets made it a key electrical insulator long before it became a collector mineral.

Quick answer: Quartz is the raw material for silicon chips. Purified quartz is smelted with carbon into metallurgical silicon, refined

Quick answer: “Rockhound” began in the early 1900s as slang for petroleum geologists in American oil fields. By the mid-twentieth

Quick answer: The Tucson Gem and Mineral Show began in 1955 as a small show hosted by the Tucson Gem

Quick answer: Some minerals are common and others are rare because of element abundance. Oxygen and silicon make up roughly

Quick answer: Concretions are hard, rounded masses that form inside sedimentary rock when minerals such as calcite, iron oxide, or

Quick answer: Banding in minerals records changes during growth. Each layer marks a shift in the fluid’s chemistry, temperature, or