As an adjective calcareous
is resembling or containing calcium carbonate or limestone; chalky.
As a noun gypsum is
a mineral consisting of the hydrated calcium sulphate when calcined, it forms plaster of paris.
gypsum
English
Noun
(
en noun)
A mineral consisting of the hydrated calcium sulphate. When calcined, it forms plaster of Paris.
Derived terms
* gypsum board (panels)
* gyprock
* gypsic