Minerals Guide (+ Identifier)

This is basically just linking Wikipedia articles. However, it is very organized, and it's easy to find what you're looking for. Nice clean format. Has an ID picture for most listings. This is more for quick reference scientific information. Under each rock/mineral, it lists category, Moh's hardness, crystal system, color, formula, fracture, luster, steak, specific gravity, and tenacity. Finally at the bottom there's a link to the Wikipedia article for it, for more in-depth information.

Minimal guide ok for free but not worth buying. One pic per mineral which does not show range of appearance and often is very unrepresentative e.g Schorl. . Some listed items are apparently missing e.g Silver. Photo should at least be zoomable. As another reviewer pointed out- inconsistencies with formulas in terms of subscripts. Plus side is it saves using a book ( though its infinitely more limited), operation is fast and interface is clean.

Good for gemologists, terrible for people who want to identify items in their yards. Non-zoomable pictures, no sorting by colors unless you know all color variations and hardness of the mineral. Missing many pictures of some of the possibilities.