The LBMA said refiners it accredits, which dominate the industry and supply the world's biggest banks, jewellers and manufacturers, processed 4,836 tonnes of gold in 2018 -- an amount worth around $300 billion at current prices.
It said 2,127 tonnes came from large industrial mines, 26 tonnes was supplied by small and artisanal mines, and 2,683 tonnes was recycled gold such as jewellery, bars and coins returned to the market to be melted and refashioned.
The disclosure was part of the LBMA's first annual report on the implementation of its responsible sourcing guidelines, which aim to stop gold whose production is linked to human rights abuses, crime or environmental damage from entering the supply chain.
Artisanal and recycled gold is riskier than that from large mines because it often passes through many different hands and its origins can be difficult or impossible to trace.
The LBMA says its refiners process more than 90% of gold from large industrial mines, but they take only a tiny fraction of the roughly 550 tonnes produced by artisanal and small scale miners each year.
The bulk of this gold is processed by refiners outside the LBMA system who are often less concerned with its origin. It can then move through the market labelled as recycled gold.
The LBMA said in the report it is aware of the risks of recycled gold and as well as developing its own rules is working with authorities in countries with large refining industries to improve regulation.
(Reporting by Peter Hobson; editing by Emelia Sithole-Matarise)
