- Feldspar (/ˈfɛl(d)ˌspɑːr/ FEL(D)-spar; sometimes spelled felspar) is a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the plagioclase (sodium-calcium) feldspars and the alkali (potassium-sodium) feldspars. Feldspars make up about 60% of the Earth’s crust, and 41% of the Earth’s continental crust by weight.
- Lincoln County — Thumbnail History (historylink.org)
Lincoln County, formed in 1883, is located in northeast Washington in the region historically known as Big Bend Country. The county measures 2311.2 square miles, ranking it seventh in size among Washington’s 39 counties.