The softest mineral in the world is called Talc. It has a Mohs hardness of 1, which means it can be easily scratched with a fingernail. Talc is a hydrated magnesium silicate mineral that is commonly used in cosmetics, paper, and ceramics due to its softness and ability to absorb moisture. It is also used as a filler and lubricant in products such as rubber and plastics. Talc can be found in many parts of the world, including the United States, China, and Brazil.