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 Upper Crust (band) The Upper Crust (band) The Upper Crust is an American hard rock band from Boston, Massachusetts. The members adopt the personae of 18th century aristocratic fops and sing songs from that perspective. They use titles of nobility, wear powdered wigs and period costumes, and maintain a snobbish attitude both during live performance and on their albums. The members say that their guiding philosophy is "if not great and excellent, then debauched." Their major music influence is Bon Scott-era AC/DC, along with glam rock band Kiss and fictional heavy metal band Spinal Tap. "Rolling Stone" wrote, "[d]ismiss Boston's Upper Crust as