Gypsum. Polarised light micrograph of a thin section of gypsum. Gypsum is a chemical sedimentary rock,composed mainly of hydrated calcium sulphate. It may grow as a crystal aggregate (as here) or in giant tabular crystals up to 1 metre in length. Gypsum is used in plaster of Paris,in Portland cement and as a flux in pottery. The most compact form of gypsum is known as alabaster. Object size: 5 mm | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Pasieka, Alfred |
Taille de l’image : | 4781 px × 3655 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |