Gold Refining

We can supply various size of gold refining plants and for turn-key projects. Our strong cooperation with manufacturer of machines for the precious metals, will give best benefits to Client for their different type of projects. Project financing via barter is negotiable.

Refining tumbler unit

This refining system consists of a hollow PPL tumbler with a total volume of about 100 litres and a useful capacity of about 50 litres (acids plus gold grains). The tumbler is inclined at 25° and continuously rotates by means of a special motor. The rotation speed can be regulated.The continual rotation causes the gold grains to rub against each other and consequently the dissolution time is considerably shorter.

External to the tumbler there is a Pyrex-glass fume condenser with water circulating inside. Another advantage is that this unit can work without supervision.

The maximum daily quantity you can refine every day is of 12 kg (6 kg per cycle) of gold grains getting a final gold purity of 999,5/1000 (minimum).

It is a multi-purpose unit allowing the user to refine the gold grains as well as casting scraps and some types of precious ashes.

The plant is mainly made up of:

Polypropylene hood designed to the recover any acid losses
PPL tumbler with a useful capacity of about 100 litres
No. 2 Graduated tanks for HCl and HNO3.
No. 1 PPl tray where two 100 lt containers for HCl and HNO3 acids are stored.
No. 2 Filter units on wheels with a compressed air diaphragm pump to transfer the solutions. One 450 mm high, the second 750 mm.
No. 1 100 lt cementation unit.
No. 1 Control panel

The plant is mainly made up of:

Precious metal assay lab brief info

Introduction to Assaying

The assaying process is a necessary step to determine the quantity of precious metals present in an alloy. Cupellation is one operation of the assay process in which a sample of gold, wrapped in lead foil, is melted in a special crucible known as a cupel: this cupel has the capacity of absorbing the non-precious metals contained in the gold alloy. The weight of the gold alloy sample is usually about 250/1000. Although this is the most ancient method to determine the purity of an alloy, assaying by means of cupellation gives greater precision than more modern methods (fluorescent or x-ray spectrophotometry) and is considerably less expensive.

NOTE: The standard assay laboratory can carry out approx. 40 assays per day. It is possible to increase this number by using a multiple assay hood (for example model CS/D) in place of the CS/D unit and by purchasing a larger cupellation furnace (for example, model FCOPP/B).