Gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO. 2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard/sidewalk chalk, and drywall.
Magnesite
Magnesite is a mineral with the chemical formula Mg CO3 (magnesium carbonate). Iron, manganese, cobalt and nickel may occur as admixtures, but only in ... Crystal class: Hexagonal scalenohedral (3m); H-M symbol: (3 2/m)
Crystal habit: Usually massive, rarely as rhombohedrons or hexagonal prisms Space group: R3c Solubility: Effervesces in hot HCl
ENVIRONMENT MANAGEMENT
Good practice in action: mines address environmental impact
Responsible mining companies have developed, or are developing, detailed environmental management policies based on industry best practice. These govern their operations and how they affect the environment, setting out clear goals and commitments.The following are some of the key areas covered, with examples of the action large mining companies are taking:
Hazardous materials, waste and chemicals
Companies draw up detailed plans for handling these substances listing all the potentially hazardous materials, waste and chemicals used in, or produced by, their operations. The plans include measures to manage their use and mitigate their effects. For example, rigorous safety procedures and controls cover the storage, transportation, handling and use of explosive materials. Environmental management of waste also influences the rehabilitation of areas affected by mining tailings.
Water conservation and management
Water is both a key component in many mining activities and a key consideration in the task of minimising environmental impact. Responsible mines have detailed plans for conserving local water supplies, managing their own use, and ensuring that local supplies are not polluted. Therefore, detailed water-management plans will cover water conservation, water quality and toxicity. They may also help companies target reductions in their use of water.
Occurence of Gypsum
“A Common mineral,with thick and extensive evaporite beds in association with sedimentary rocks.” Gypsum is deposited in lake and sea water.Hydrothermal anhydrite in veins is commonly hydrated to gypsum by groundwater in near surface exposures. Often associated with the minerals halite and sulfur.