Black-Gray Slate Metamorphic Rock 1-2 Inch, 2 Pieces
by American Educational Products

A fine-grained, layered metamorphic rock, Slate is derived from a shale-type of sedimentary rock composed of either clay or volcanic ash. Because low heat and pressure are also used to form Slate, fossils have been found within it, up to and including microscopic remains of some delicate organisms. It is mainly composed of an amalgamation of minerals, such as quartz, muscovite and illite to name but a few.

It has been used throughout the ages in a number of different capacities, from roofing to flooring tiles, and in tandem with chalk as a notepad. Because of its thermal stability and being relatively chemically inert, Slate has found use as drink coasters, bench tops in laboratories and and as billiard table tops. Some high-quality pieces of slate are also used as tombstones and commemorative tablets. 

• Each rock is approximately 1-2 inches on the longest side.
• Thickness ranges from around 1/2 cm to 1 cm.

Origin: VT