What is non-hydraulic cement?

Syed Sabaat Answered First
Non-hydraulic cements include such materials as (non-hydraulic) lime and gypsum plasters, which must be kept dry in order to gain strength, and oxychloride cements, which have liquid components. Lime mortars, for example, "set" only by drying out, and gain strength only very slowly by absorption of carbon dioxide from the atmosphere to re-form calcium carbonate through carbonization.

What is cement?

Cement is a building material made by grinding calcined limestone and traces of clay and gypsum. Its key use is as an ingredient for concrete or mortar.

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