What Type of Rock Is Rainbow Slate?

Slate Rock

• Slate rock is a low-grade, foliated metamorphic rock that can be easily split into thin pieces along the natural folds in the stone. Slate rocks are made through the "low-grade regional metamorphism," of shale, fine-grain tuffs mudstones and other pelithic sediments, according to Rocks-Rock.com. In laymen's terms, this means that the banded appearance of rainbow slate rocks have been created out of the heat, direct pressure and other chemical processes the stone has been exposed to while buried deep in the Earth.

Rainbow Slate

• A cream to light tan base color intersected with bands of browns, oranges, whites and reds distinguishes rainbow slate rock from other stones. It is also characterized by its brittle nature, which can result in sharp edges when broken in nature or intentionally. The fact that the colors of rainbow slate appear crisper and brighter in clear water makes it a staple in aquarium and aquatic decor.

Where It's Found

• Major quarries of rainbow slate are located throughout the U.S., Canada, England, India and Australia. In the U.S., stone-smiths who regularly work with rainbow slate can be found in California, New York, Montana, Georgia and Pennsylvania, but you can order rainbow slate rock, tiles and craft pieces from various online sources.

Uses

• Rainbow slate rock is used to make individual tiles of various sizes, tabletops, countertops and shelves. Its distinctive color and pattern, as well as its easy ability to be broken, shaped and sanded, gives rainbow slate great appeal to artists and craftsmen. Broken pieces are also used as decor items in terrariums and reptile tanks as well as fresh and saltwater aquariums as some fish, like angelfish, catfish and discus, prefer to lay their eggs on flat surfaces.