"Geopolymers are new materials for fire- and heat-resistant coatings and adhesives, medicinal applications, high-temperature ceramics, new binders for fire-resistant fiber composites, toxic and radioactive waste encapsulation and new cements for concrete. The properties and uses of geopolymers are being explored in many scientific and industrial disciplines: modern inorganic chemistry, physical chemistry, colloid chemistry, mineralogy, geology, and in other types of engineering process technologies. Geopolymers are part of polymer science, chemistry and technology that forms one of the major areas of materials science. Polymers are either organic material, i.e. carbon-based, or inorganic polymer, for example silicon-based. The organic polymers comprise the classes of natural polymers (rubber, cellulose), synthetic organic polymers (textile fibers, plastics, films, elastomers, etc.) and natural biopolymers (biology, medicine, pharmacy). Raw materials used in the synthesis of silicon-based polymers are mainly rock-forming minerals of geological origin, hence the name: geopolymer. Joseph Davidovits coined the term in 1978^[1] and created the non profit French scientific institution (Association Loi 1901) Institut Géopolymère (Geopolymer Institute).
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Egyptian Pyramid stones

With respects to archaeological applications, in the mid-1980s, Joseph Davidovits presented his first analytical results carried out on genuine pyramid stones. He claimed that the ancient Egyptians knew how to generate a geopolymeric reaction in the making of a re-agglomerated limestone blocks.^[44] The Ukrainian scientist G.V. Glukhovsky endorsed Davidovits' research in his keynote paper to the First Intern. Conf. on Alkaline Cements and Concretes, Kiev, Ukraine, 1994.^[45] Later on, several materials scientists and physicists took over these archaeological studies and are publishing their results, essentially on pyramid stones.^{[46][47][48][49]}"  (Source)