Refining Systems Used to Make Gold Bars - Chemical Treatment

Refining gold using chemicals is another common method. Gold is treated with sulphuric, hydrochloric or nitric acids.

Refining Systems Used to Make Gold Bars - Cupellation

As the ore melts, the slag that floats on the top of the mixture contains impurities which have been drawn out of the gold ore.

Revenueland - help to reuse valuable materials which would otherwise be wasted

Recycling of metals in order to successfully recover raw materials from urban mines, a systematic recycling approach with effective recycling schemes is necessary.

Revenueland - Refine AU's areas of expertise within raw materials recycling cover the following metal groups:

◉ Rare metals (RE, In, Ta, Li)

◉ Light metals (Al, Mg, Ti)

◉ Precious metals (PGM, Ag, Au)

◉ Base metals (Cu, Zn, Pb)

Fire Assay / Cupellation - Cupels for assays and refining noble metals

Cupellation was one of the most common processes for refining precious metals. By then, fire assays were used for assaying minerals. Cupellation is still in use today.

Elemental Purities by ICP - Inductively Coupled Plasma-Optical Emission Spectrometry

Final Analysis: The Role of Inductively Coupled Plasma-Optical Emission Spectrometry in Determining the Fineness of Precious Metals