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[Construction Section 149]

In general, gypsum colorless or white, but by inclusion of foreign ions or impurities of different kinds, like for example sand or bitumen and other, a red, yellow, gray or brown color accept. His stroke color but white.
Gypsum is often massively, in fine form, as a colorless, white, yellow, red or gray alabaster. In fine and fibrous form gypsum fiber or atlas spat it also.

In todays construction is gypsum, as hemihydrate or multi-phase plaster, usually in the form of special gypsum, so like as artificial plaster, plasterboard walls for intermediate as well as for plasterboard for dry, as a raw material for various plasters and dry strokes.
In addition, there will also be a primer and filler. By mixing with lime produced one of lime plaster stucco work, which is shaped like plasticine before cure.

Because the assembled cast some water solubility, it will only predominantly gypsum building materials for the interiors were used. In a secure outdoor area must be impregnated plaster building materials.

Previously, for gypsum plaster work on facades, and impregnated with linseed oil. Stuck as a material is very good for commissioned work on walls and ceilings to use. Because gypsum hygroscopic, which means water-absorbing, and is therefore in bad installation, poor maintenance or ventilation to discoloration and building uf fungus inclined, it is in wett cels and in the basement area of only limited use.