Minerals

What is Velvet Malachite

Velvet malachite is a textural habit of the copper carbonate hydroxide mineral malachite (Cu₂CO₃(OH)₂), defined by extreme…

How to Tell If a Rock Is Worth Money

When you find an unusual or eye-catching rock and wonder if it might be valuable, the first step is careful observation and …

How to Identify Quartz

Learning how to identify quartz is one of the most practical skills in geology and rock collecting. Quartz is among Earth’s…

What Are Pyrite Ammonites

Pyrite ammonites are fossilized shells of extinct marine mollusks whose original material has been replaced or coated by ir…

Purple Fluorite: Color & Properties

Purple fluorite is the violet to deep-purple variety of the halide mineral fluorite (calcium fluoride, CaF₂). Its vivid col…