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Refining plants

The process of Gold atrifacts or Silver artifacts always begins with Gold Refining or Silver Refining.
The metal which goes to the refining plant comes from gold mining and silver mining and they are in the form of dorè ingots.
Otherwise the raw material is in the form of gold scraps coming from jewellery, goldsmith, silversmith or photographic and electonical components production.
The raw material is refined in 2 different ways: either with the Aqua Regia method or with the Electrolytic Refining.
The assay process is the step that establishes the fineness of the refined metal.

The Acqua Regia Method
The purpose of the refining process is to obtain the gold or silver with purity not less then 995/1000 from the raw material.
The most commun gold fineness are:
- Au995
- Au999
- Au9999
- Au99999
The most commun silver fineness are:
- Ag999
- Ag9999

The chemical process uses Aqua Regia which attacks the raw material. The refining process has different steps, the very first is the assay process which defines the grade of the raw material to be treathed.

The lowest grade of the alloy which can be refined are:
Au not less then 650/1000
Ag not more then 100/1000

  • Production process

  • Gas furnace to recover the metal

  • Tilting melting furnace to make the metal drops, the liquid metal falls into a water tank to fo form flat drops and then it goes into the refining plant with the ragia water
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The Electrolysis Method

The refining electrolytical process in done by dissolving a non-pure gold anode into an electrolytical solution. In the refining electrolytical process the metal to be purified is melted into an anod (strip) and another thin sheet of the same metal works as cathode.
Assaying laboratory for test the fineness of the refined gold or silver.

  • Electrolytical Plant
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  • Assaying laboratory for final grade
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