Hydrated normal sulphate, blödite group
Specific gravity: 2.23
Hardness: 2½ to 3
Colour: Colourless, bluish-green, reddish; colourless in transmitted light.
Solubility: Readily soluble in cold water
Blödite occurs in lacustrine salt deposits and salt efflorescences, probably as a product of metamorphism of marine salt deposits,
in nitrate deposits, and it may be a volcanic sublimate. In marine salt deposits associated minerals include
carnallite and polyhalite. In lacustrine salt
deposits associated minerals include halite, thénardite
At the type locality, Ischler Salzberg, Perneck, Bad Ischl, Gmunden District, Upper Austria, Austria, blödite occursin an oceanic salt deposit (Mindat).
Dehydration, which is endothermic, occurs at 107oC and 227oC; the first product is löweite; at the second step this transforms into α-Na2Mg2(SO4)3 and vanthoffite or thénardite (Mindat).
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