A metamorphic rock that's formed from shale is slate. Slate is a low-grade rock that's used as a building material. It is often used for roofing tile because of the ease with which it can be split into thin sheets. If slate is installed properly, it's also waterproof.
Slate is created when shale is compressed under moderately high temperatures. This compression can be due to the movement of the earth in a process called dynamic metamorphism. The pressure causes water to be squeezed out of the rock and the tiny clay mineral or mica grains in the shale to line up at right angles to the direction of the pressure. The pressure can also cause the resulting slate to be foliated. This means its materials are arranged in parallel bands.
Slate is often a gray rock with a matte luster and a very fine grain. It can also be green, black or purple. Slate quarries are found in Cornwall and the Lake District in England as well as Italy, Portugal, Brazil, Vermont and New York state. Slate was traditionally used for blackboards as well as roofing tiles.
Fossils are often found in slate. However, sometimes the formation of cleavage, or the plane through which the rock naturally breaks, deforms the rock to the point where any fossils are destroyed.Learn More
Metamorphic rock is formed underground through a process that changes a rock's molecular structure due to pressure, heat and chemical reactions. A metamorphic rock forms from a parent rock called a protolith. Depending on conditions, a protolith can transform into any metamorphic rock. Because protoliths are capable of undergoing vast changes, identifying them is sometimes difficult for geologists.Full Answer >
Marble is a metamorphic rock formed from limestone. Changes in the limestone's chemical properties due to external forces can result in the creation of marble.Full Answer >
Shale forms from the pressure of layers of sediment compressing bits of silt that settle into the clay on the bottom of bodies of water. The compressed clay and silt become shale over time. Shale is a sedimentary rock.Full Answer >
Talc is a metamorphic rock, which means it was originally a different kind of rock that changed under heat and pressure. Talc is composed of hydrated magnesium silicate, and its chemical formula is Mg3Si4O10(OH)2.Full Answer >