Glendonite is the name given to the pseudomorphic calcite after ikaite. Ikaite, a hexahydrated calcium carbonate, was first observed in nature in the 1960s, at the seabed of the Ikka Fjord in Greenland. There, it precipitates due to the mixture of cold water submarine springs (3°C) rich in carbonates with seawater. Ikaite deposits are not usually found due to its poor stability, however, sometimes the rapid conversion of ikaite to calcite and water results in the generation of pseudomorphic calcite aggregates in the shape of the ikaite crystal (so-called glendonites). These calcite pseudomorphs directly replace ikaite above 4ºC.