Economic geology is concerned with earth materials that can be used for economic and/or industrial purposes such as metals, nonmetallic minerals, construction-grade stone, petroleum, natural gas, coal, and water.
Mining Geology is an applied science which combines the principles of economic geology and mining engineering to the development of a defined mineral resource to economically extract the ore. The mining of sand, gravel, building stones, non-metallic minerals, metal ores, coal etc. apply various principles and techniques.
Gemology or gemmology is the science dealing with natural and artificial gemstone materials. It is considered a geoscience and involves the exploration, mining, cutting, polishing and quality testing of gems.