Igneous Rocks (most important ones for us underlined)

Intrusive Extrusive

Granite Rhyolite(Quartz, K feldspar, Na Plagioclase)Light in color, often pinkish, with few dark minerals

Diorite Andesite(Na,Ca Plagioclase, Biotite, Hornblende)Intermediate in color, “salt and pepper” for diorite, dark to light gray for andesite

Gabbro Basalt(Ca plagioclase, pyroxene, olivine)Dark in color, usually black, gabbro has shiny crystals

SEDIMENTARY (most important ones for us underlined)

(uniform layering on a large and small scale)

Clastic

Conglomerate (grains bigger than 2mm)Sandstone (grains .06mm to 2 mm)Siltstone (grains .002mm t0 .06mm)Shale (grains less than .002mm)

Chemical

Limestone (CaCO3)Dolostone (CaMg (CO3)2)Halite (NaCl)Gypsum (CaSO4.2H2O)

Metamorphic (most important ones for us underlined)

(Produced from pre-existing rocks of all kinds by heat, pressure and shearing. Often layered, but distinguished from sedimentary rocks by wavy foliation)

Slate (slightly metamorphosed shale, dull, no crystals visible)

Phyllite (more metamorphosed shale, shiny, but crystals still too small to distinguish easily)

Schist (still more metamorphosed shale, shiny highly foliated, mica usually obvious, individual crystals easily seen)

Gneiss (very highly metamorphosed shale, sandstone or igneous rock of various types, often banded with not so obvious foliation)

Marble (metamorphosed limestone)