Minerals & Gems Database

An open, growing reference of minerals and gemstones — each with a photo, chemical formula, Mohs hardness, crystal system, colour and a description. Compiled from diverse academic, governmental and other public-access sources, it covers identification (formula, mineral group/class), physical properties (hardness, crystal system, lustre, streak, density) and typical occurrence — curated and expanded incrementally.

Open data from Wikidata (CC0); mineral photographs from Wikimedia Commons, each under its own licence — open an entry and follow the image link for its author and licence.
This is an open-data reference for education and triage. It is not a valuation, an authentication, or gemmological certification.