The gold-mining unit of one of China's top miners has launched a $3.2bn initial public offering in Hong Kong, taking advantage of record high prices of the precious metal to fund its expansion.

Zijin Mining is offering around 349mn shares at HK$71.59 each to raise HK$25bn, according to a listing document released on Friday. The unit will be listed as Zijin Gold on the Hong Kong Stock Exchange.

The listing comes as gold is punching through record highs of more than $3,600 a troy ounce, with geopolitical tension and macroeconomic uncertainty fuelling the metal's rally.

The IPO will be the biggest in the world since a $5bn share offering in May from CATL, the globe's largest battery maker, which also took place in Hong Kong.

The city-state's benchmark Hang Seng index is among the best-performing indices this year, as a wave of Chinese companies list on the bourse.

Singapore's sovereign wealth fund GIC, BlackRock, Schroders and Oaktree are among the more than two dozen cornerstone investors to the deal. Cornerstone investors have subscribed about $1.6bn to the IPO. Morgan Stanley and Citic Securities are joint sponsors of the offering.

Zijin Mining is China's top gold producer and has mining operations spanning China, central Asia, Colombia, Serbia, Ghana and Australia.

According to the IPO prospectus, Zijin Gold will be "formed by combining all of the gold mines of Zijin Mining located outside of China". Zijin Gold said it produced 40.4 tonnes of gold (1.3mn troy ounces) in 2024.

Zijin Mining subsidiaries will be the controlling shareholder of the gold spin-off with a 86.7 per cent stake in the new business.

In recent years, Zijin said it had acquired underperforming gold mines "due to scarcity of high quality gold mines as acquisition targets". It said it improved production through "technological innovations, production expansion, and enhanced operational efficiency".

The company said proceeds from the share sale would be used to settle the acquisition of a gold mine in Kazakhstan, develop a mine in Ghana and invest in a mine in Suriname.

Gold has doubled in value since the start of 2023 and now trades around $3,648 a troy ounce. The rise in prices has been driven by increased central bank buying as well as from demand from investors seeking a hedge against geopolitical and macroeconomic uncertainty.

Last year, bullion overtook the euro as an official reserve asset for central banks.

China gold miner boosts Hong Kong with $3.2bn listing