"WardsSci000764"

Breccia is a sedimentary rock made up of angular rock fragments.

Gray to white metamorphosed carbonate rock.

Calcite is a translucent calcium carbonate mineral, mohs hardness 3.

Gray to tan clastic rock made of silt sized particles.

Obsidian is hard black colored, volcanic glass.

Massive sedimentary gypsum with a moh's hardness 2..

Gray metamorphosed shale showing "slaty cleavage".

Metamorphosed rock showing foliation and rich in hornblende.

Conglomerate is a sedimentary rock made up rounded quartz pebbles.

A textbook example of pure crystalline carbon which is extermely soft.

Massive white quartz with a moh's hardness 7.

Selenite is a Clear gypsum mineral with a moh's hardness of 2.

Scoria is a dark-colored rock formed from lava with a high gas content.