Feldspar 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 metamorphic rock. Rock formed almost entirely of calcic plagioclase feldspar (see below) is known as anorthosite. Feldspars are also found in many types of sedimentary rocks. The name "feldspar" derives from the German "Feldspat", a compound of the words "Feld", "field", and "Spat", "a rock that does not contain ore". The change from
The Cyborg from Earth The Cyborg from Earth The Cyborg from Earth is a 1998 science fiction novel by Charles Sheffield. It is the fourth in a series of unrelated stories, published by Tor Books in their Jupiter line. The novel starts in a future dystopian Earth where the upper class lives a life of privilege, while most others live in the "pool", an endless crowd of unemployable youths depending on government assistance or crime for survival. The book is told from the perspective of the main character, Jefferson Kopal, a young member of an immensely wealthy and powerful spaceship building family founded by