Billionaires investing in a luxury London home would have had higher returns from gold in the fixtures and fittings than the property itself in the past decade, according to Knight Frank.

A typical so-called super-prime property in London’s Kensington district would have cost 24,000 ounces of gold 10 years ago, compared with about 9,800 ounces now, Knight Frank says in a report. “To visualise this, 9,800 ounces would be a cube about the size of a small footstool, admittedly a heavy one,” the London-based real estate broker says.