The minerals are organized by chemical type, oxides, sulfides, etc. The photos are acceptable quality, but not remarkable. It contains almost no associated mineral information. The section on rocks may actually be more informative with reasonable photos, and small enhancing drawings providing additional information. Organized by chemical composition.
Photos are above average typically two minerals per page.
Only one photo of each mineral type. Good supply of typical mineral data, with a drawing of crystal structure for each mineral. The rock photos are excellent. Photos are good for gemstones, and there are often two or more for any given material. The physical property data takes up about 1 page on average for a mineral type, and then often several more pages describing characteristics of type members.