What this site is
A free reference of minerals and gem materials. Each page reprints one English Wikipedia article’s property table and lead paragraph word for word, credited on the page. Nothing here is medical, legal or financial advice: the figures are for information only, and a page describes a material, not a treatment and not a purchase.
Licence
Text and property values adapted from Wikipedia are available under CC BY-SA 4.0. See the licence text. Where a sentence or a value came from a Wikipedia article, that article is linked on the same page and the revision id is named there. Reuse must keep the attribution and the same licence, as CC BY-SA 4.0 requires.
Accuracy
Values are reprinted exactly as the fetch recorded them, at the revision named on each page. Wikipedia articles change; a page here shows the article as it was at that revision, fetched 2 October 2026. The site is provided as is, without warranty. To report a mismatch between a page and its source revision, write to editors@almanacdesk.com.
Third parties
No crystals are sold here, no commissions are taken and no affiliate links are placed. Trademarks and trade names that appear inside a quoted article belong to their owners.