If anyone can afford to take the long view on investment, it’s surely the British monarch. Queen Elizabeth II on Wednesday passes Queen Victoria as the longest-reigning British head of state, after 63 years on the throne.

She has seen 13 prime ministers, 12 US presidents and the invention of modern portfolio theory. Her predilection for horseracing is well known. But how’s her investment strategy? She has little choice in asset allocation. The castles, the crowns, the 3,000-carat Cullinan diamond and much else are held in trust, and cannot be rebalanced into equities. Valuation is tough, too, with 17th century royal headwear even less liquid than junk bond ETFs.

Still, the portfolio has a useful bias towards inflation protection, and assets that appeal to the burgeoning super-rich. There is no index of crown jewels, but the sterling gold price has more than doubled in real terms. Diamonds have turned out to be less flashy, lagging inflation.