A valuation model Harvey proposed in a National Bureau of Economic Research study 18 months ago, when gold was nearly $1,700 an ounce, correctly foresaw that the metal was overvalued.

That model is based on the tendency for gold to decline whenever the ratio of its price to the consumer-price index rises well above its average level of about 3.4, and to rise when it is significantly below that average. With the CPI now at 237.1, this ratio stands at 5.6.

To be sure, Harvey acknowledges, gold is perfectly capable of taking a long time to return to its fair value — and by no means will the path it takes be a straight line. So a near-term rally isn’t out of the question