Diamond price indices are increasingly quoted alongside gold and silver

Wealth and investment commentary is starting to cite polished diamond price indices alongside gold and silver, though the two behave very differently as assets.

• Gold and silver trade on transparent, continuously quoted spot markets; diamond price indices are built from a sample of wholesale transactions and lag real-time pricing.
• Diamonds are not fungible the way bullion is — two stones of the same carat weight can differ in value by a large margin depending on cut, colour and clarity.
• Treating a diamond index the way you'd treat a spot gold price risks overstating how liquid or comparable individual stones actually are.

A diamond can be a good store of value in a specific stone bought well, but it isn't a substitute for a liquid commodity market. Ask the trade desk before treating any index figure as a resale guarantee.