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
Salting the earth Salting the earth Salting the earth, or sowing with salt, is the ritual of spreading salt on conquered cities to symbolize a curse on their re-inhabitation. It originated as a symbolic practice in the ancient Near East and became a well-established folkloric motif in the Middle Ages. The custom of purifying or consecrating a destroyed city with salt and cursing anyone who dared to rebuild it was widespread in the ancient Near East, but historical accounts are unclear as to what the sowing of salt meant in that process. Various Hittite and Assyrian texts speak of ceremonially strewing salt, minerals,