The pearl, nicknamed the Sleeping Lion because of its unusual form, had been expected to fetch up to €540,000.

The jewel is thought to have formed during the reign of the Qianglong emperor between 1700 and 1760 and was originally plundered by a Dutch merchant from Chinese waters in 1765.

Chinese law at that time stated that all large pearls were the property of the emperor. A decade later it was acquired by the Russian empress Catherine the Great for her collection at the Hermitage.

More recently it belonged to an Amsterdam-based family of jewellers for four generations before passing into the hands of its current owners, the Amsterdams Parel Genootschap.

The society is pleased with the sale, but told ANP it was like ‘a child leaving home’. ‘You want to be sure they get there safely.’