The tip of a spiral shell has broken off and become a grain of sand. It is opalescent from the repeated tumbling action of the surf. Surrounding the shell fragment are five other sand grains, from top middle clockwise, (1) a pink shell fragment, (2) a foram, (3) a microscopic shell, (4) a volcanic melt, and (5) a bit of coral. Image Copyright © 2008 Dr. Gary Greenberg, All Rights Reserved.
Sand from Skeleton Beach in Namibia contains rounded and polished pink-and-red garnet. Image Copyright © 2008 Dr. Gary Greenberg, All Rights Reserved.
Sand from Zushi Beach, Japan, contains what looks like a sapphire crystal. The crystal is larger than the surrounding grains and has survived eroding because of its hardness and quality. Image Copyright © 2008 Dr. Gary Greenberg, All Rights Reserved.
The glacially deposited sands around Lake Winnibigoshish, Minnesota, contain abundant sediments from the igneous and metamorphic minerals of the Lake Superior basin. A sample includes pink garnets, green epidote, iron-rich red agates, black magnetite, and hematite. Image Copyright © 2008 Dr. Gary Greenberg, All Rights Reserved.
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