Online College Courses for Credit

2 Tutorials that teach Geology: Rock Classification Overview
Take your pick:
Geology: Rock Classification Overview

Geology: Rock Classification Overview

Author: Nathan Lampson

This lesson will present how to identify and classify various rocks and minerals.

See More
Fast, Free College Credit

Developing Effective Teams

Let's Ride
*No strings attached. This college course is 100% free and is worth 1 semester credit.

47 Sophia partners guarantee credit transfer.

299 Institutions have accepted or given pre-approval for credit transfer.

* The American Council on Education's College Credit Recommendation Service (ACE Credit®) has evaluated and recommended college credit for 33 of Sophia’s online courses. Many different colleges and universities consider ACE CREDIT recommendations in determining the applicability to their course and degree programs.



Characteristics for identifying and classifying types of rock:



Crystals have flat surfaces.  The flat surfaces of crystals are shiny and may sparkle.



Geodes appear as round, hollow rocks that contain crystals.  Geodes are caused by minerals seeping into cracks between rocks and forming crystals.



Soft and sometimes crumbly rocks that are formed in layers over a long periods of time.



Rock with layers that look like ribbons and may contain crystals.  Metamorphic rock is formed below the earth's surface due to heat and pressure.



Igneous rock formed from lava that is cooling quickly is smooth, glasslike, and may contain tiny bubbles.  When igneous rock is formed slowly within the earth, the rocks have a coarse mineral texture.

Geology: Rock Classification Overview