Macro photograph of a cross-sectioned carnelian geode; carnelian is a variety of chalcedony, which is a variety of quartz; from Washington State Image #2896 5769 X 4612 pixels
Macrophotograph of quartz on fluorite (calcium fluoride); Green Fluorite Mine, Manaoshan Mountain; Hunan, China Image #4137 3094 X 4622 pixels
