Rock & Mineral Encyclopedia

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

Montana Moss Agate

A translucent chalcedony from Montana filled with black and red dendritic inclusions that look like moss, ferns, or scenic landscapes.

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

Tourmaline crystals displaying two or more distinct colors at once, including the famous pink-and-green watermelon variety.

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