Gypsum *Selenite

Solution. Dissolve lOO gm. of the commercial salt in 1000 cc. of water. Let the solution stand a day, and then filter if not clear. Calcium Sulphate, CaS04. — Solid. For water of crystallization use crystallized gypsum (selenite). For other work use the powdered variety. 

Occurs only in combination, as limestone, marble, chalk (GaCO,) gypsum, selenite, alabaster (CaSO,), aud many other minerals. In bones, egg-shells, oyster-shells, etc., as Ca,(PO,), and CaCO and in many vegetable structures... 

Payena /eer///Sapotaceae) Gutta Sundek gypsum (selenite)... 

Synonyms anhydrous calcium sulfate-anhydrite muriacite karstenite anhydrous gypsum anhydrous sulfate of lime hemihydrate-plaster of Paris annalin dried gypsum dried calcium sulfate dihydrate-gypsum alabaster satin spar mineral white terra alha satinite light spar selenite precipitated calcium sulfate native calcium sulfate... 

Lome Sulphate of Lime 4 Calcareous earth Selenite, gypsum Calcareous vitriol... 

Gypsum white or grey CaS04 2 H20 Ba, Sr, Mg Also called hydrated gypsum, lime, gips, selenite New York, Maryland, Oklahoma... 

It would not suffice to have decomposed gypsum, to have demonstrated separately the mixts that compose it, to have demonstrated that it was formed by the union of vitriolic acid with a calcareous earth, in a word that gypsum was nothing other than selenite it would still be necessary to take the materials nature employed, recompose a new gypsum which would produce the same effects, which would give the same phenomena. ... 

Examine specimens of selenite, gypsum, and plaster of Paris. Describe them. Recall or repeat the experimental study of the solubility of calcium sulphate. Mix a little plaster of Paris with enough water on a block of wood to form a thin paste. Let it stand undisturbed for ten or fifteen minutes, and then examine. Describe the change. What is meant by the set of plaster of Paris ... 

Calcium sulfate dihydrate alabaster Cal-Tab-, Compactroh, Destab-, E516 gypsum light spar mineral white native calcium sulfate precipitated calcium sulfate satinite satin spar selenite terra alba USG Terra Alba. 

Subaqueous lacustrine gypsum is commonly prismatic, typically a few millimetres in size but ranging from 100 pm to several metres (Mees, 1999 Warren, 1982). The larger, vertically oriented crystals are commonly referred to as selenite. 

Apart from the Raman spectroscopic identification of two different types of bacteria in a gypsum crystal Nostoc and Gloeocapsa), it was also possible to detect organic signatures from bacterial colonies sited several millimetres below the surface in a transparent crystal of selenite from a 26 Mya meteoritic impact crater [37] at Devon Island in the Canadian High Arctic (Figure 1-9). 

Figure 1-9. (Selenite var. gypsum) deposits, Haughton meteorite impact crater, Devon Island, Canadian...

Calcium sulphate CaS04.2H2 Bihydrate of Itme calcic sulphate gypsum plaster of Paris selenite sulphate of lime. 

Dihydrate, native calcium sulfate precipitated calcium sulfate gypsum alabaster selenite terra alba satinite mineral white satin spar light spar. Lumps or powder, d 2.32. It loses only part of its water at 100-150. Sol in water very slowly sol in glycerol. Practically insol in most organic sol -vents. 

Selenite The clear colorless variety of gypsum, which typically forms large euhedral crystals. 

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