Gypsum (Selenite)
Hydrogenous sedimentary rock.
Selenite is a common form of mineral form gypsum (CaS04 nH20) and can be found in many locations throughout the western United Stats. Selenite forms from evaporative concentration of salty water (such as seawater, lake water, or groundwater). It can accumulate in desert dry lake beds.
Clear selenite sheets is also associated with arid soil weathering in hillsides in arid regions. This sample came from of weathered Cretaceous shale beds in the Panoche Hills, central California. |
| https://gotbooks.miracosta.edu/rocks/sedimentary/15.html |
2/2/2021 |
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