Aragonite

Aragonite is a calcium carbonate mineral, with a hardness of about 3.5 on the Mohs scale. It is a common component of limestone, and can also be found in cave deposits, hydrothermal veins, and hot springs. Aragonite is an important component in the formation of coral reefs, as it is secreted by coral reef animals and microorganisms to form the structure of the coral reefs. Additionally, aragonite is used in a variety of commercial applications, such as the manufacture of cement, glass, and fertilizer. It is also used in aquariums, as the addition of aragonite helps to increase the pH level of the water and maintain the calcium level, making it an important mineral for the health of aquarium fish.