Diamond shipments have come to a "standstill", industry traders warn, as demand for the stone drops down dramatically. Following Donald Trump’s global tariffs, shipments through Antwerp, one of the world’s busiest centers for the gems, are down one-seventh of usual levels.

Despite minerals such as gold and copper being excluded from America’s levies, diamond imports have been hit with the 10% tariff, as well as a suggested "retaliatory" charge on certain countries. The US is the world’s largest customer of the stone, which makes up half of worldwide demand. Due to its lack of diamond mines, Mr Trump’s country relies solely on foreign imports. The Belgian city of Antwerp is one of the hardest hit by the levy as its diamond shipments have "ground to a halt" following the announcement, Karen Rentmeesters, chief executive of the Antwerp Diamond Centre said.

"It’s disrupting the industry," she told the Financial Times, adding how it makes "no sense" for her country’s diamonds to be included in the US tariffs. Ms Rentmeesters drew comparisons between the current level of sales to the Covid-19 pandemic when shipments plummeted. "Everything literally ground to a halt," she said.

Prior to the tariffs, the industry had already taken a hit from both coronavirus and the competition of lab-grown diamonds. Chair of the mining company Trustco Resources, Richard Chetwode, told the outlet that trade is "not in a good place". "If you are suddenly putting tariffs on it, you are crucifying it."

The United States’ role in the supply chain of diamonds comes at the very end for the certification process. The largest agency in the world is the Gemological Institute of America (GIA), based in California.

Prior to this, the stones are produced in one country, traded in another and polished in a third before ending up in America.

Chief operation officer at the GIA, Pritesh Patel, said that his company is looking into whether diamonds imported to the US just for certification could be exempt from tariffs.

Mr Patel also said GIA is currently extending their services in other countries to accommodate some of the impact from the tariffs.