Minerals Project for Science

Igneous Rock

Igneous rocks are made up of non living things.

Pegmatite -a coarsely crystalline granite or other igneous rock with crystals several centimeters to several meters in length

Andesite - a dark, fine-grained, brown or grayish volcanic rock that is intermediate in composition between rhyolite and basalt

Basalt -a dark, fine-grained volcanic rock that sometimes displays a columnar structure. It is typically composed largely of plagioclase with pyroxene and olivine

Peridotite - a dense, coarse-grained plutonic rock containing a large amount of olivine, believed to be the main constituent of the earth's mantle

Pumice - a very light and porous volcanic rock formed when a gas-rich froth of glassy lava solidifies rapidly.


Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form".

Slate - a fine-grained gray, green, or bluish metamorphic rock easily split into smooth, flat pieces

Phyllite - a fine-grained metamorphic rock with a well-developed laminar structure, intermediate between slate and schist in degree of metamorphism.

Schist - a coarse-grained metamorphic rock that consists of layers of different minerals and can be split into thin irregular plates.

Gneiss - a metamorphic rock with a banded or foliated structure, typically coarse-grained and consisting mainly of feldspar, quartz, and mica.

Marble - a hard crystalline metamorphic form of limestone, typically white with mottlings or streaks of color, that is capable of taking a polish and is used in sculpture and architecture.


Sedimentary rocks are types of rocks that are formed by the depositions of material at the Earth's surface and within bodies of water.

Conglomerate - a number of different things or parts that are put or grouped together to form a whole but remain distinct entities.

Breccia - rock consisting of angular fragments cemented together.

Sandstone - sedimentary rock consisting of sand or quartz grains cemented together, typically red, yellow, or brown in color.

Shale - soft, finely stratified sedimentary rock that formed from consolidated mud or clay and can be split easily into fragile slabs.

Siltstone - fine-grained sedimentary rock consisting of consolidated silt.