Chalcedony Properties: Hardness, Varieties and Formation
Chalcedony is a microcrystalline silica material that includes agate, onyx, carnelian and many other familiar stones....
Crystal Properties
Explore the physical properties of crystals and minerals, including hardness, fluorescence, structure, transparency, and composition.
Moonstone Properties: Hardness, Composition and Glow
Moonstone is an adularescent feldspar known for a floating white or blue glow. Learn about its composition, hardness,...
Tiger’s Eye Properties: Hardness, Formation and Chatoyancy
Tiger’s eye is a chatoyant quartz material known for its moving golden-brown band of light. Learn about its compositi...
Labradorite: Properties, Labradorescence and Spectrolite
Labradorite is a plagioclase feldspar renowned for its shifting flashes of blue, green, gold and other colours. Disco...
Obsidian Properties: Volcanic Glass, Hardness, Types and Care
Discover how obsidian forms, why it is volcanic glass rather than a mineral, and what creates its black colour, glass...
Rose Quartz Properties: Colour, Hardness, Asterism and Care
Explore rose quartz properties, including its pink colour, Mohs hardness, inclusions, crystal structure and occasiona...
Clear Quartz Properties: Hardness, Structure, Fluorescence and Care
Discover clear quartz and rock crystal properties, including composition, Mohs hardness, crystal structure, transpare...
Amethyst Properties: Hardness, Colour, Fluorescence and Care
Discover amethyst’s mineral properties, including its composition, Mohs hardness, crystal structure, purple colour, U...