Rocks! Flashcards
Granite
Igneous
coarse grained
primarily orthoclase and quartz, with biotite and hornblende
Mainly yellowish white, lightly speckled with large black bits (reflective)
(like syenite but more quartz present)
Syenite
Rock
Igneous
coarse grained
primarily orthoclase, with biotite and hornblende
light grey rock with lots of dark small specs (reflective)
Rhyolite
Igneous
fine grained
primarily orthoclase and quartz, with biotite and hornblende
pinkish-brown with random reflective specs
Gabbro
Igneous
coarse grained
Mainly pyroxenes with plagioclase
predominately black with grey and white specs (reflective)
Basalt
Igneous
fine grained
Mainly pyroxenes with plagioclase
Black (dull)
Obsidian
Igneous
Glassy
Mix of orthoclase, quartz, plagioclase, biotite, and hornblende
Black and glassy!!
Gneiss
Metamorphic
coarse, medium, and fine
mainly quartz, feldspar, and micas
made from granite
colored banding!!
Phyllite
Metamorphic
fine granular
clay (not noticeable) and mica (noticeable)
silky sheen, splits with flakes, thin layers, grey with yellowish white
Marble
Metamorphic
coarse to fine
calcite, dolomite, serpentines
made from limestone
Blend of colors (no speckling, more like gradients). observed rock is mix of white, orange, and brown
Slate
Metamorphic
fine granular
minerals not visible
made from shale
smooth cleavages, thin layers, smoother than shale. Observed rock is dark grey
Schist
Metamorphic
coarse, medium, fine
mainly schist with mica
mica is super noticeable (very reflective). Color is tan with grey/black speckling (layers on side)
Shale
Sedimentary
fine
made of silts and clays
often grey, can be white, red, green, or black
White Sandstone
Sedimentary
Coarse
main component is quartz
Very sadly and crumbly, light color
Limestone (Calcitic)
Sedimentary
Fine
high amounts of calcium carbonate
dark grey with rust colored patches
Limestone (Dolomitic)
Sedimentary
Fine
high amounts of calcium carbonate
yellow with rust colored patches