BLM What is Selenite? How does Gypsum BLM Lands Benefit form? Americans This mine contains a deposit of a Gypsum is commonly The BLM strives to transparent, crystalline formed in highly be a good neighbor form of gypsum evaporative within its communities called “selenite” environments, such as by balancing land (CaSO4·2H2O). closed-basin lakes. In conservation with these lakes, a water multiple use. All varieties of gypsum source terminates are very soft minerals. in the lake basin. The BLM provides In fact, the most Dissolved ions within opportunities for local important identifying the water concentrate economic growth and characteristic of in the basin. As sustainability in areas gypsum is its hardness. water evaporates, the such as recreation, If you find a clear minerals precipitate ranching, forest and mineral, try scratching out of the water woodland products, it with your fingernail. and form solid salts, mining, and energy Gypsum has a hardness including calcite, development. BLM of 2 on Mohs Hardness gypsum, and halite lands provide valuable, Scale (see below), (table salt). An tangible goods which is softer than example of this type that surrounding your fingernail. Other of environment is the communities rely on transparent minerals, Great Salt Lake. and use every day to such as quartz and heat homes, build and varieties of mica, This selenite was maintain roads, and are harder than your deposited as part feed families. fingernail and will not of the Moenkopi be scratched. Formation during the Please help the BLM early Triassic about 250 with its mission to million years ago for sustain the health, several million years. diversity, and At this time, a large productivity of the basin existed over the public lands for the southern portion of use and enjoyment Strip Field Office Arizona Fingernail Utah and this area of of present and future northern Arizona. generations. Copper Coin Knife / Glass Steel Mohs Hardness Scale www.thegemchronicles.com Map at time of deposition 250 million years ago (Paleogeography of Southwest North America ©2012 Colorado Plateau Geosystems Inc.).