The qualitative sorting consists in identifying the manufacturing defects on luxury glass bottles, perfumes, cosmetics, top-of-the-range spirits, according to standards of calibration, weighing and aspect, and to classify them, good or bad, according to the customer’s specifications. This sorting requirement, which can lead to the elimination of perfectly good items, contributes to the reputation of the Bresle Valley.
Most of the time, a first sorting is done at the glassmakers who invest more and more in automatic sorting machines using cameras and powerful computers that allow to eliminate the most common defects. Teams or companies specialized in manual sorting will intervene, where automatic machines are currently inoperative. These are most often surface defects or defects in the distribution of the glass mass, the degree of tolerance of which is provided by the glassmaker, a toolkit that will enable operators to keep only those bottles that can be marketed.
The percentage of eliminated bottles, the “rejects”, can be very variable from one bottle to another but in any case these non-conforming bottles will be recycled. The white glass is melted down in the glassmakers’ furnaces and is called “cullet”. It has the advantage of lower energy consumption in the melting process. Bottles for the pharmaceutical industry are sorted in “clean rooms” to avoid the presence of any impurity.