PCBs (printed circuit boards) are boards made of insulating material (mainly glass-epoxy laminates (TSE) or composite materials), covered with a thin layer of copper foil, onto which a pattern of paths constituting electrical connections is printed. There are also conductive elements made of nickel, silver, gold and tin on their surface.
Processing of printed circuit boards and integrated circuits begins with partly manual and partly automated dismantling of devices containing PCBs. The next stage is sorting tiles by metal content into categories. The basic division concerns the gold content, based on which we distinguish: low-grade (with a gold content of 0-50 / 70g gold per ton), mid-grade (70-120g gold per ton) high-grade (with a gold content> 120g gold per ton). The number of product categories depends on the purpose, with a detailed breakdown we can distinguish several dozen items. The range is normally cleaned of aluminum and iron parts.