The calcination of limestone is one of the oldest technical processes and it is still of actual interest. Very early calcitic mortars from Turkey have been investigated and compared with materials of other early civilisations i.e. with Egyptian mortars containing gypsum as well as medieval dolomite-based mortars from alpine regions. Contemporary calcination procedures, in particular the cement production, range among the most important global industrial processes causing non neglectable environmental problems. Sustainable, solar energy assisted calcination technologies and the conversion of product CO2 into useful commodities are discussed.