Refinery

A refinery (also called an affinery) is a specialist plant that recovers precious metals from impure feedstock and works them up into high-purity fine metal. The idea of "separating" refers to parting the metals from one another — gold from silver, copper or platinum, for example.

What refineries process

The raw material comes from two sources:

• Primary material: doré bars and concentrates straight from mining.
• Secondary material (recycling): dental gold, jewellery and broken gold, industrial scrap, catalytic converters and electronic waste.

From this mixture emerge fine gold (999.9), fine silver and the platinum-group metals at standard commercial purity — as bars, granules or casting material.

How refining works

The classic routes are refining by chemistry and electrolysis. In the Miller process, chlorine gas is passed through molten gold to bind off foreign metals; the Wohlwill process uses electrolysis to reach the highest purities above 999.9. Silver is usually refined electrolytically. Only this purity turns the metal into market-ready goods whose value is measured precisely against the spot price.

Why refineries matter to sellers of scrap gold

Anyone selling scrap gold is, in effect, selling into the material cycle of the refineries. Reputable buyers determine the fineness by assay and pay out a fair share of the material value. Some refineries also buy directly from private individuals — often on better terms than intermediaries, because one trading step is cut out. What is realistic can be checked with the purchase-price calculator; the pure material value comes from the melt value calculator.

LBMA Good Delivery

The most respected refineries are listed on the Good Delivery List of the London Bullion Market Association. Bars from these houses are regarded worldwide as beyond question and need not be re-tested on resale — a mark of quality that also improves the resaleability of investment bars.

In brief

Refineries stand at both the beginning and the end of the precious-metal cycle: they turn ore and scrap gold back into tradeable fine metal. For sellers of broken and dental gold they are — directly or through buyers — the decisive source of value.