Ivory marked by the Royal African Company. International Slavery Museum, Liverpool. Wikimedia Commons.
Official gold stayed at $35 for governments, and everyone else got a market price.
If money is tight, this is distant until the dollar in your pocket buys less.
If you are in the middle, a currency with two prices is a currency people are starting to doubt.
If you have savings, gold and the dollar are no longer the same promise.
In March 1968 the London gold pool collapsed and the official link held only for central banks.
Private buyers paid whatever the market asked.
The Bretton Woods price was still $35 an ounce on paper, and already a fiction in the street.
Source: Federal Reserve and Treasury history of the London Gold Pool and the March 1968 two-tier gold market.