Every day, there are a whopping 5,500 tonnes ($212 billion) of gold traded in London, making it the largest wholesale and over-the-counter (OTC) market for gold in the world.

To put that in perspective, Visual Capitalist's Jeff Desjardins notes that more gold is traded in London each day than what is stored at Fort Knox (4,176 tonnes). On a higher volume day, amounts closer to total U.S. gold reserves (8,133.5 tonnes) can change hands.

How is this possible?

The infographic below tells the story about gold’s foremost trading hub, as well as the paper gold market in London, England:

London is dominant in global price discovery for gold.

In 2015, it accounted for roughly 88% of gold trade – most of which occurs between banks on behalf of their clients. Further, 90% of London trade is spot trading, which further emphasizes London’s importance in price discovery for gold markets.

While the high-level details of the market are visible, the individual mechanisms behind the London gold trade are less clear. There is very little detailed information provided on physical shipments, outstanding gold deposits or loans, allocated or unallocated gold, or clientele types. Trade reporting also breaks down at a more granular level, and datasets on the GOFO (Gold Forward Offered Rate) were also discontinued in January, 2015.

Almost all gold (95%) traded in London is unallocated and without legal title. This makes it easier to trade, but it also raises concerns about a market that is opaque to begin with. There are 5,500 tonnes of paper gold exchanging hands on paper each day, but there are only 300 tonnes of gold vaulted in London outside of the reserves for ETFs or the Bank of England.

What would happen if there was ever even a small rush to get the physical asset behind the paper? Is there a system in place for such an event, and how does it work?

Original graphic by: BullionStar