Feldspar (including electrical insulators, sanitaryware, pottery, tableware, and tile) and other uses, such as fillers, accounted for the remainder. In earth sciences and archaeology, feldspars are used for K-Ar dating, argon-argon dating, and luminescence dating. In October 2012, the Mars Curiosity rover analyzed a rock that turned out to have a high feldspar content. Feldspar Feldspars (KAlSiO – NaAlSiO – CaAlSiO) are a group of rock-forming tectosilicate minerals that make up about 41% of the Earth's continental crust by weight. Feldspars crystallize from magma as veins in both intrusive and extrusive igneous rocks and are also present in many types of
Primary minerals in the acidic igneous rocks and a second group of accessory minerals which were formed by deposition from the residual mother liquors. Modern soil science offers the following definition: "Primary Minerals: The thickness of the earth's crust varies from 10 km under the ocean to 30 km under the continents. Of the 88 naturally occurring elements on earth, only 8 make [up] most of the crust. The earth's crust and soils are dominated by the silicic acid in combination with Na, Al, K, Ca, Fe and O ions. ...Those elements are components of primary minerals, whereas primary minerals are components