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What is slate? Tell me about it.
Slate is a metamorphic rock that is formed from the contact metamorphism (high pressure and heating) of the sedimentary rocks shale, mudstone or siltstone on the edges of mountain regions. Sometimes the original bedding of the shale can be seen in the slate. Slate has a fine-grained texture (the crystals are too small to see) and is often dark, blue-gray in color but also may be green, brown or red. The major minerals contained in slate are quartz, feldspar, carbonates (such as calcite), chlorite and micas. Slate can be easily broken into sheets along “cleavage planes.” Because of its properties, slate can be used as a building material for roofs and flooring and for gravestones. Slate is often found in France, Finland, United States, and England.
