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Vicat Prompt is an almost instantaneous setting and fast hardening natural cement made from a unique limestone with no additives such as Pulverised Fuel Ash (PFA), Fly Ash, or Portland Cement. Not to be confused with modern “Portland” cements, Vicat Prompt is made by firing an argillaceous limestone from a homogenous rock strata at low temperatures (800C-1200C) and then grinding the result to a very fine powder. Vicat Prompt has been manufactured from the same limestone uninterrupted for over 150 years. In fact, Vicat’s production facility still utilizes kilns from the 1870’s in the production of Vicat Prompt. This singular limestone deposit in the French Alps and the mineralogical and chemical makeup is consistent, precise, and ideal for the making of natural cements free of external additives. Vicat Prompt Natural Cement is a product of France.

Care must be exercised when specifying or using Natural Cements in restoration or preservation work. Traditionally, Natural Cements were used in a variety of applications, but they should never be viewed as a cure all. Always examine existing conditions and the structure before specifying or using any replacement mortar. However, Vicat Prompt is an ideal choice of binder when very fast setting/hardening is required and where, adhesion, long term strength, resistance to corrosive water or sea water, and waterproofing is needed.

In 1812, Louis J. Vicat, engineer to Napoleon, began research into the nature and hydraulicity of limes and (natural) cements. The results of his research were published in 1828 and reprinted with additional information in 1856. In his works he notes that over 900 producers were manufacturing limes and hydraulic binders in France. Today one company, a company which bears Louis Vicat’s name, is still producing traditional natural cement. Vicat was founded in 1853 by Joseph Vicat (son of Louis Vicat) and is still managed to this day by the Vicat family. Vicat has over 150 years of unparalleled experience, support, and technical data with Natural Cement.

Prompt Technical Information

Where to Use
Vicat Prompt Natural Cement can be used to gauge traditional lime mortars and plasters, as well in situations that require rapid setting or exceptionally high compressive strengths.
Vicat Prompt Natural Cement is made from an extremely hydraulic agrillaceous limestone that is fired at low-moderate temperatures and then ground to a powder.