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industry and the private household sector. Therefore it is particularly sustainable to return these expensive residues to the use-cycle of precious metals by
reclaiming the contained pure metals such as gold, silver, platinum, palladium and rhodium (<xr id="fig:Precious_metals_in_various_forms"/><!--(Fig. 11.1)-->).
Precious metal recycling is nowadays closely related to the protection of the environment. It is integrated into a complex network of processes that benefit the clean supply of water and protection of the air quality. The wastewater streams generated during refining processes are treated by special processes which remove hazardous components. High efficiency wet scrubbing and filtration of exhaust air is employed in all stages of the metal recycling processes.
<figure id="fig:Precious_metals_in_various_forms">
[[File:Precious metals in various forms.jpg|rightleft|thumb|Figure 1: Precious metals in various forms]]
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==<!--11.2-->Refining Methods==
The precious metal containing products and materials submitted into the refining process are generally called precious metal scrap (<xr id="fig:Examples_of_precious_metal_scrap"/><!--(Fig. 11.2)-->). They are usually classified into three categories which differ by the refining processes employed and by the cost-to-value ratio.
<figure id="fig:Examples_of_precious_metal_scrap">
[[File:Examples of precious metal scrap.jpg|left|thumb|Figure 2: Examples of precious metal scrap]]
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Main Articel: [[Refining Methods| Refining Methods]]
==<!--11.3-->Recommendations for Scrap Handling==
==<!--11.4-->Refining Costs==
Melting costs are only charged for re-meltable scrap and are based on the gross weight of scrap delivered, as well as on the type of precious metal to be recovered. The processing required for palladium containing scrap is, for example, significantly more complex that the one for silver containing metal scrap.
Preparation costs are only assessed for the refining of low grade (sweeps) scrap and are grouped into quantity breaks. They cover all processing steps such as burning, shredding, milling and blending, up to the point of sampling.
Fees for the cost of content analysis vary by the type of precious metal and the form of the sample. Ash samples require significantly more work than pure metallic materials due to their high content of mineral substances.
The actual cost of refining includes all separation steps and processes required to recover the precious metals. They are grouped into two sub-categories:
These include all processing steps for the actual refining of the different metal components included in the scrap. The are charged according to the starting gross weight or the scrap weight after melting.
This amount contains the costs for transforming the refined metals into the required grade of purity, and also the cost to convert the end metal product into a commercially re-usable form such as for example ingots or granulate.
==<!--11.5-->Precious Metal Crediting Options==