Skip Navigation LinksDEP > Citizens > Just For Kids > Mines > What are Mines

What are Mines?

mines collageWhat are mines?

Mines are holes that are dug to remove valuable minerals from under the ground.

Pennsylvania has very rich deposits of valuable minerals including coal, limestone, iron ore and slate. Early settlers dug and burned coal to heat their homes and businesses. Pennsylvania is now a major supplier of coal for generating electricity and making steel. Limestone is important for making steel, glass, roads and concrete. High-quality slate from Pennsylvania was shipped around the world for roofs and foundations. Other valuable products from Pennsylvania's mines include clay, sand and gravel.

Mining has been one of the most important industries in Pennsylvania for over 300 years. The Pittsburgh Coal Seam is one of the most valuable and heavily mined mineral deposits in the world.