Rock-Forming Minerals PDF
Document Details
Tags
Summary
This document provides information on rock-forming minerals, including their characteristics, chemical compositions, and physical properties. The document details various examples such as quartz, feldspar, mica, etc. It's likely educational material focused on geology or science.
Full Transcript
ROCKS a natural substance made up of crystalline crystals of various minerals fused together form a solid mass MINERALS CHARACTERISTICS OF A MINERAL: 1. Naturally Occurring 2. Inorganic 3. Solid MINERALS CHARACTERISTICS OF A MINERAL: 4. Orderly Crystalline Structure 5. Definite Chemical Composit...
ROCKS a natural substance made up of crystalline crystals of various minerals fused together form a solid mass MINERALS CHARACTERISTICS OF A MINERAL: 1. Naturally Occurring 2. Inorganic 3. Solid MINERALS CHARACTERISTICS OF A MINERAL: 4. Orderly Crystalline Structure 5. Definite Chemical Composition ROCK-FORMING MINERALS 1) QUARTZ chemical composition: SiO2 Mohs Scale: 7 highly fragile 1) QUARTZ hard, glassy substance with white streaks Pure quartz is transparent and clear. 2) FELDSPAR chemical composition: XAl12Si32O8, where X is K, Ca, or Na Mohs Scale: 6 fairly tough 2) FELDSPAR light-colored material, usually white, but milder colors of red or green are possible 2) FELDSPAR a glassy luster has rectangular crystals that shatter along flat faces 3) MICA set of hydrous potassium aluminum silicate minerals Mohs Scale: 2 to 2.5 3) MICA perfect cleavage, which reduces it to thin smooth flakes Its shine is responsible for the flashes of light in rocks such as granite and slate. 4. PYROXENE chemical composition: XY(Al,Si)2O6, with X being Ca or Mg and Y being Mg, Fe, or Al Mohs Scale: 5 to 6 4. PYROXENE has a glassy sheen with white, pale green, or light brown streaks key feature: two cleavages at around 90° 5. AMPHIBOLE chemical composition: X(OH)4Si16O44, with X being Mg, Fe, or Ca Mohs Scale: 5 to 6 5. AMPHIBOLE has a dark color has a transparent appearance and a glassy gloss has very long and thin crystals 6. OLIVINE chemical composition: (Mg, Fe)2SiO4 Mohs Scale: 6.5 to 7 distinctive olive-green hue 6. OLIVINE translucent, glassy substance that is nearly as hard as quartz Its crystals are granular in appearance. 7. CALCITE chemical composition: Ca(CO3) Mohs Scale: 3 7. CALCITE found in abundance in sedimentary rock limestone and metamorphic rock marble 7. CALCITE with three cleavage directions that intersect at 75-degree angles
