Mr. Longoria's Earth Science

 Clear quartz showing crystal shape What is a Mineral? All the rocks and minerals of Earth's crust consist of elements.  An element is a substance that cannot be broken into simpler substances by ordinary chemical means. A mineral is a naturally occurring inorganic solid with a definite chemical composition and an orderly arranged atomic structure.  Most minerals are compounds (two or more elements chemically combined).  More than 90 percent of the minerals in Earth's crust are compounds containing oxygen and silicon, the two most abundant elements. How Minerals Form Minerals form in several ways.  Many form out of magma (molten rock), in which atoms and ions move freely.  As magma cools, the atoms and ions move closer together and form chemical bonds that create compounds.  The rate at which magma cools determines the size of the minerals grains (crystals) that form.  Mineral forming processes can be gradual and lengthy.  Ame...

Minerals are naturally occurring homogeneous inorganic solids that have a definite chemical composition and an internal arrangement of atoms. Although about 3000 minerals have been identified and classified, less than a dozen are found commonly. One of the most common minerals on the surface of the earth is quartz (SiO2). The image shown on the side is an Amethyst crystal, which is the purple variety of quartz. Homework - Due Tuesday, November 17, 2009: In textbook, read chapter 5, pages 90-91; 96-98; do questions 1and 2 on page 95 and questions 1-3 on page 102.

Minerals are naturally occurring homogeneous inorganic solids that have a definite chemical composition and an internal arrangement of atoms. Although about 3000 minerals have been identified and classified, less than a dozen are found commonly. One of the most common minerals on the surface of the earth is quartz (SiO 2 ). The image shown on the side is an Amethyst crystal, which is the purple variety of quartz. Homework - Due Tuesday, November 17, 2009 : In textbook, read chapter 5, pages 90-91; 96-98; do questions 1and 2 on page 95 and questions 1-3 on page 102.