There are many different types of rocks, minerals and stones out there. Each falls into a particular category and is used for certain purposes. One of the more popularly used rocks out there, slate has created a number of mining industry devotees to it across the world.

Slate rock is an example of a sedimentary rock. It gets formed from either clay or volcanic ash that has been superheated and pressurized underground.

Under the sun, slate rock's gray coloring looks slightly wet and slick. The grains of the rock are very small, and sometimes bits of quartz embedded in the rock can be seen.

The construction of roofs and floors uses much of the world's quarried slate rock. It lasts much longer than artificial construction materials and is generally sturdier.

Nations across the globe operate slate quarries. The finest slate is said to come from Wales, the United Kingdom, Portugal, Brazil, Vermont and New York.

Three types of slate quarries exist: underground, open and pit. Underground quarries have mines running into rock where slate is found, open quarries mine the slate from the sides of cliffs, and pit quarries are found where a slate deposit dips vertically.