Selenite (mineral) was filled with mineral-rich water that drove the crystals' growth. The largest of those crystals weighs 55 tons, is long, and is over 500,000 years old. Gypsum occurs on every continent and is the most common of all the sulfate minerals. Gypsum is formed as an evaporative mineral, frequently found in alkaline lake muds, clay beds, evaporated seas, salt flats, salt springs, and caves. It is frequently found in conjunction with other minerals such as, copper ores, sulfur and sulfides, silver, iron ores, coal, calcite, dolomite, limestone, and opal. Gypsum has been dated to almost every geologic age since the
Alpine vegetation of Tasmania Oxford University Press, Inc. Seymour, D.B., Calver, C.R. (1998) Time and Space diagram. Mineral Resources Tasmania and AGSO 1998. Slatyer, R. (2010) Climate change impacts on Australia’s alpine ecosystems. The ANU Undergraduate Research Journal 2, 81-97. Tranquillini, W. (1964). The physiology of plants at high altitude. Annual Review of Plant Physiology 15, 329-346. Williams, P.R. (1977) Geological survey of Port Davey. Tasmania Department of Mines. Alpine vegetation of Tasmania Alpine vegetation refers to the zone of vegetation between the altitudinal limit for tree growth and the nival zone. Alpine zones in Tasmania can be difficult to classify owing to Tasmania’s