Rock & Mineral Encyclopedia

Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.

Microcline

A common potassium feldspar identical in composition to orthoclase but more ordered, famous for its green gem variety amazonite.

A prized Idaho jasper known for porcelain-smooth pastel pinks, creams, and greens in soft swirling, orbicular patterns.

A man-made opalescent glass that glows milky blue in reflected light and warm orange when backlit, often sold as a crystal.

Smithsonite is a zinc carbonate ore famous for glassy botryoidal crusts in blue-green, pink, and yellow hues.

A group of silicate gemstones best known for deep red but spanning nearly every color, including green tsavorite and orange spessartine.

A sought-after elbaite tourmaline in teal hues that blend blue and green, prized for its ocean-like color.

A precious opal showing dominant peacock-like blue, green and teal play-of-color, often on Ethiopian material.