Researches into possibility of application of Lithuanian anhydrite

Abstract

As of 2010 it is foreseen to start the mining of anhydrite rock from the underground Pagiriai anhydrite deposit, previously explored in a detailed way, and as of 2012 its operation on a large scale. This rock is very pure and decorative. The article provides the results of investigations on application of natural anhydrite, which have been carried out in the VGTU Scientific Institute of Thermal Insulation. It is established that next to well-known non-hydraulic anhydrite binding material, it is possible to produce a strong hydraulic composite binder out of non-burnt natural anhydrite to replace Portland cement in certain fields of application. As a sulphate retarder of setting, anhydrite can be used for production of common cement. For these purposes, of use is also the top layer of deposit consisting of anhydrite and gypsum rock mix. The investigations showed that anhydrite powder of high whiteness (> 90 %) can serve as filler in the production of finish putties, oil paints, as well as for surface whitening of paper and carton. A strong spotted anhydrite of dense crystalline structure is fit for production of cut finish panels and other stone articles.