| |
| |
Slate - Wikipedia, the free encyclopedia |
 | | Slate is a fine-grained, homogeneous, metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low grade regional metamorphism. |
 | | Slate is mainly composed of quartz and muscovite or illite, often along with biotite, chlorite, hematite, and pyrite along with, less frequently, apatite, graphite, kaolin, magnetite, tourmaline, or zircon. |
 | | Slate is also found in the Arctic and was used by the Inuit to make the blades for ulus. |
| en.wikipedia.org /wiki/Slate (455 words) |
|