Igneous rocks

Rocks do not have a definite composition of mineral constituents. Feldspar and quartz are the most common minerals found in rocks. There are many different kinds of rocks which are grouped under three families on the basis of their mode of formation.

List of all Igneous, Sedimentary, and Metamorphic Rock Types with Pictures and Links to Specific Articles about each Type of Rock.

Illustrated overview and examples of igneous rocks: basalt, granite, obsidian, pumice, gabbro, porphyry...

Trap rock is a construction industry term for dark-colored igneous rocks such as basalt, gabbro, and diabase that are used to make crushed stone.

Obsidian is a glassy igneous rock that usually forms as an extrusive lava.

In short, if you want to know what igneous rock is and how it formed, you can just imagine a volcanic eruption. But if you have more curiosity, you want to know the gritty details of how something viscous becomes rock. What happens on the surface as the lava and ash settle into their new states? Do rocks form in magma chambers below? Here is a detailed guide on what igneous rocks are and how they form. For more, check Outforia's latest article to find out!

The three main types of geological rocks are described. They are...

Photographs and descriptions of intrusive and extrusive igneous rocks with photos and links to detailed articles by Geology.com

Pictures, Definition, Classification, Composition, Geology, and Occurrence of Peridotite.

Rhyolite, extrusive igneous rock that is the volcanic equivalent of granite. Most rhyolites are porphyritic, indicating that crystallization began prior to extrusion. Crystallization may sometimes have begun while the magma was deeply buried; in such cases, the rock may consist principally of