As explained in the general introduction, considering the fine fraction of crushed demolition concrete as alternative raw materials for Portland clinker production is one of the three options for recycling concrete. This way of recycling sands from crushed concretes 64is based on the rough assumption that the chemical and mineralogical composition of a given concrete is mainly governed by the nature of the coarse and fine aggregates, which can be assumed in first approximation as siliceous-calcareous (even if in some geographical regions, pure limestone or pure siliceous aggregates can be found), which brings into the chemical system the desired main elements: calcium and silica. The potential value of the use of an alternative raw material for Portland clinker production is a classic problem which can be solved by applying a semi-experimental approach. In this approach, a set of a few experiments can determine, from the chemical composition of each material used, the quantitative proportions of the raw components through the calculation of the potential composition of the future clinker (Bogue 1929) and the burnability indices. This approach has been implemented using a calculation sheet under MS-Excel run under Solver in order to maximize the replacement rate of raw materials by Recycled Concrete Sands (RCS) in optimizing the potential composition of the clinker and the burnability indices. In this chapter, we present the technological evaluation of the opportunity to use the fine fraction extracted from crushed demolition concretes as Alternative Raw Materials (ARM) for Portland Clinker production. The above methodology has been successfully applied to recycled concretes from four geographical areas in France (with four distinct geological contexts), followed by a full-scale industrial Portland clinker production.