Rock #’s 1-5

ROCK SPECIMEN

MINERAL COMPOSITION

FORMATION AND CHARACTERISTICS

Granite

feldspar, quartz, mica

intrusive rock with larger crystals usually lighter colored

Rhyolite

feldspar, quartz, mica

extrusive rock with the same composition as granite

Obsidian

quartz, alkali feldspar

extrusive natural glass with few or no visible crystals

Basalt

calcic plagioclase, clinopyroxene

extrusive dense rock usually high in iron and magnesium content

Scoria

feldspar, augite, horneblende

extrusive rock ejected from volcano cooling so rapidly gas bubbles are trapped within it

Which of the three types of rock were rocks 1-5?________________________

Rock #’s 6-10

ROCK SPECIMEN

MINERAL COMPOSITION

FORMATION AND CHARACTERISTICS

Limestone

calcite, dolomite

fossil marine plant and animal remains

Sandstone

quartz, calcite, hematite

forms from the compaction of sand and has a high quartz content

Tufa

calcium carbonate, silica

formed near hot springs or percolating ground water

Shale

various

compacted clay, silt or mud that usually has is found in sheets

Conglomerate

various

compacted river gravel or beach particles

Which of the three types of rock were rocks 6-10?_______________________

Rock #’s 11-15

ROCK SPECIMEN

MINERAL COMPOSITION

FORMATION AND CHARACTERISTICS

Gneiss

quartz + feldspar/mica

foliated rock with small crystal formation

Slate

mica + original rock

foliated rock with a possible parent rock of Shale

Shist

mica, amphiboles, pyroxene

foliated rock with a possible parent rock of sandstone or shale created under tremendous heat and pressure creating broad crystal bands

Quartzite

quartz

nonfoliated rock changed from parent rock of sandstone into a much harder rock that breaks into jagged pieces

Marble

calcite, dolomite

nonfoliated rock from parent rock of limestone that is very hard, but can be carved and polished

Which of the three types of rock were rocks 11-15?______________________