Obsidian, Marble, and Sandstone... O my!

Obsidian:
- Igneous rock

Obsidian

- Forms above the surface
- Normally black in color

The above information was received from: http://geology.com/rocks/obsidian.shtml

Marble:
- Metamorphic rock
- Forms in exposed regions of tectonic plates
- Light colored

Marble

The above information was received from: http://geology.com/rocks/marble.shtml

Sandstone:
- Sedimentary rock
- Formed from compressed sand, held together by clay/silt
- Forms wherever large amounts of weathered sediment collects and is pressurized
The above information was received from: http://geology.com/rocks/sandstone.shtml

Sandstoen

Link to soil orders: http://www.cals.uidaho.edu/soilorders/orders.htm
Link to Soil Triangle: http://www.oneplan.org/Water/soil-triangle.asp