Garnet is an important silicate rock-forming mineral and occurs in many rock types. However, it almost never makes up the majority of the rock’s mass. The same is true with a garnet-bearing sand. Garnet is a common mineral in sand but usually in low quantities. There are some hard to find exceptions – red and very beautiful sand where garnet is indeed the most abundant sand-forming mineral. Source rocks of garnet is usually either metamorphic (garnet schist, rarely eclogite) or igneous (aluminum-rich granite). Garnet sand is a sub-type of heavy mineral sand.
Garnet sand from Australia. Width of view 20 mm.
Garnetiferous heavy mineral sand sorted out by running water near the coastline of Pfeiffer Beach, California.
A macro photo of the Pfeiffer Beach sand. Most of it (pink mineral) is garnet. Width of view 8 mm.
Garnet rich sand that has metamorphosed into hard rock. Magnetite and quartz are other notable minerals. Varanger Peninsula, Barents Sea, Northern Norway. Width of sample 18 cm.
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