Selenite crystals. Selenite is a transparent and colourless form of gypsum (hydrated calcium sulphate),a common mineral deposit formed from precipitated salt (sedimentary evaporite). Gypsum has natural insulating properties,and all varieties feel warm to the touch. It is used in the making of plaster of Paris for construction,as a retarder in Portland cement,as a flux for pottery and as a fertiliser. Here one of the selenite crystals has developed in a classic 'ram's horn' shape (left) | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Wiersma, Dirk |
Taille de l’image : | 5000 px × 3574 px |
Model Release : | Non requis |
Property Release : | Non requis |
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