Sources & methods

Every value on this site traces to a source you can check. Data comes only from open-licensed or public-domain sources, each value carries its origin, and anything calculated is computed by our own documented code. Nothing is copied from other mineral websites.

Crystal structures & X-ray diffraction

Cell parameters, space groups, and atomic structures come from theCrystallography Open Database(COD), an open-access collection dedicated to the public domain (CC0) that includes the American Mineralogist Crystal Structure Database. Each mineral page names the specific COD entry used and links to it. Powder X-ray diffraction patterns are calculated from those structures (Cu Kα1, 1.5406 Å, idealized occupancies, no thermal or preferred-orientation corrections — the protocol is printed beside each pattern). Calculated density comes from the same structures.

Species list & nomenclature

The species list, formulas, IMA symbols, and status follow theIMA-CNMNC List of Minerals (July 2026), the official register of mineral species.

Physical properties

Hardness, specific gravity, color, streak, luster, and cleavage are extracted as discrete facts from public-domain references: Dana’s System of Mineralogy, 6th edition (1892) and its three appendices (1899, 1909, 1915), and Ford’s Dana’s Textbook of Mineralogy, 3rd edition (1922). Each value cites its source; where our calculated density independently agrees with a historical measurement, the value carries a corroborated badge. Values with one source are marked single source. Crystal systems are cross-checked between space-group derivation andWikidata (CC0).

Photographs

Specimen photos come fromWikimedia Commons under public-domain, CC BY, or CC BY-SA licenses only; each image shows its author, license, and source link. NC- and ND-licensed images are never used, and image licenses are re-audited against Commons periodically.

Classifications

Nickel-Strunz (10th edition) and Dana (8th edition) classification codes are reproduced as standard factual nomenclature, sourced via Wikidata.

What we do not use

No text or data is taken from webmineral.com, mindat.org, the RRUFF project, or the Handbook of Mineralogy. Those resources carry restrictive or noncommercial licenses and this site is built to remain independent of them. Wikipedia text (CC BY-SA) is likewise not reproduced here; all descriptions are written from this site’s own sourced data.

Identification tool

The ID tool ranks candidates by compatibility with your observations against this same property database. It never claims certainty: match quality is shown per property, and when no candidate fits well, it says so.