cassiterite crystal - what is a mineralcassiterite crystal - what is a mineral

What is a Mineral?

How do scientists define a mineral? Learn what minerals are made of, the difference between gemstones and minerals, and their many uses.

8 Minute Read

HomeLearning CenterWhat is a Mineral?
cassiterite crystal - what is a mineral
As the principal tin ore, cassiterite played a pivotal role during the Bronze Age (from roughly 3,300 BCE to 1,200 BCE). Tin and copper are needed to create bronze. Cassiterite crystal on matrix, Huya beryl-scheelite deposit, Huya village, Mt Xuebaoding, Pingwu Co., Sichuan Province, China, 3.7 x 3.1 x 2.8 cm. © Rob Lavinsky, Used with permission.

A Scientific Definition of a Mineral

Scientific definitions for minerals vary somewhat, but the following scientifically accepted definition is short and easy to remember.

A mineral is a naturally occurring solid substance with a definite chemical composition and a specific crystal structure.

Let’s take a closer look at each condition.

Naturally Occurring

Minerals must form through natural processes. Consequently, synthetic or lab-created materials, like lab-created corundum (ruby and sapphire), are not minerals. Although gemologists can say lab-created rubies and sapphires are real rubies and sapphires, as well as real gemstones, it would be incorrect to call them minerals. In the United States, synthetic materials with the same properties as minerals can’t be called minerals in advertisements. Mineralogists refer to these products simply as synthetic materials, even if they are physically and optically identical to minerals.

Verneuil synthetic gemstone boules
August Verneuil invented the

Olena Rybnikova, PhD

Olena Rybnikova is a gemologist and mineralogist. She has a PhD in mineralogy and petrology specializing in beryllium minerals and is a certified Applied Jewelry Professional accredited by the Gemological Institute of America. Her passion is actively promoting knowledge and appreciation of nature, geology, and gemstones.

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