earth-phenomenon: Pamukkale, 19 km (12 miles) north of Denizli, is Turkey’s foremost mine
earth-phenomenon:Pamukkale, 19 km (12 miles) north of Denizli, is Turkey’s foremost mineral-bath spa because of its natural beauty: hot calcium-laden waters spring from the earth and cascade over a cliff. As they cool they form dramatic travertines of hard, brilliantly white calcium that form pools.Pamukkale has been used as a spa since the second century BC.Spectacular, but some clarification: the waters are supersaturated with calcium carbonate, which precipitates out to form the mineral travertine, a form of limestone (i.e. calcium carbonate). There’s a very important difference chemically between calcium (a very reactive silvery metal) and calcium carbonate (a white/off-white crystalline ionic solid) that should not be overlooked. -- source link
#geology#chemistry#travertine