Macrophotograph of a cluster of peridot crystals from Arizona. Most peridot is approx. 90% forsterite which is a form of olivine with a high magnesium content. Image #4112 6063 X 3930 pixels
Closeup photograph of a Dugway geode whose cavity is lined with quartz crystals; Dugway Geode Beds, Utah Image #4119 4080 X 5904 pixels
Macrophotograph of a small portion of a Cactus quartz (a.k.a. Spirit quartz) crystal cluster with purple amethyst. The orange coloration is due to iron oxidation and small iron inclusions can be seen in the matrix of many of the crystals. From the Magaliesberg Mountains of South Africa. Imge #4116 6144 X 4040 pixels
