Aden Kahr Humans have long been fascinated by crystals. Archaeological evidence suggests our ancestors have treasured small quartz and calcite stones for at least 780,000 years, often bringing them ...

When looking at calcite under a microscope, a scientist would immediately recognize the crystalline form of calcium carbonate by its rhombohedral appearance. That is, calcite is shaped like a ...

Spots of light glinted off the faceted sides of more than a dozen calcite crystals stuck inside a small cave at the top of a steep, rocky couloir. Tom Benedict balanced on a thin log spread across the ...