This helps to illustrate one of the monetary roles of gold.

A previously successful credit based system will eventually collapse under the weight of its historical circumstances and the excesses of credit which it is sucked into at the time of its greatest success. As the process of collapse unfolds one monetary store after another demolishes savers. If they hold notional long term obligations like pensions the underwriters fail. If they hold institutional debt the issuers fail. If they hold bank notes and the banks fail. It takes very few failures before the population starts to see risk in every credit based construct. Their faith in their institutions evaporates, and they become acutely aware of the dangers of anything intangible, and anything whose supply can relatively easily be expanded. This is when they begin to think obsessively about things whose supply is subject to some fundamental limit.

It becomes possible to understand why gold re-materializes as the only good money in times of such great economic distress. During such a period the most valued asset is the one which is incorruptible, and because the scarcity of gold is almost uniquely beyond the power of men to change (and because it can be discreetly owned) it is gold which re-appears as the agent of wealth storage and transfer at the junctions between the much longer episodes of representative money.

At these relatively rare junction points, as the wheel of optimal monetary solutions turns through its phases, ownership of gold is what empowers a bold and contrarian few to take control of large amounts of capital. Even as gold comes back into vogue, so the seeds of the new representative fiat currency system which will subsequently replace it will start to germinate, for the simple reason that there is never enough gold to finance the opportunities for growth in a potentially successful economic state.

When the economic conditions are right for productive work and useful business development gold is an inferior form of money. Given two neighbouring currency systems, one gold based and one fiat, and with a decent variety of opportunities with underlying demand, the fiat system will comfortably outperform the gold system. Braver businessmen will back 2, 3 or 4 ventures at once, rather than the single project which gold allows, and they will usually win the race to the top of the economic pile.

So at least half the art is to appreciate that there is no permanent answer, and that ultimate success depends on being flexible enough to profit from a return to a token based monetary system.

Gold as a money of choice

But gold does not only appear at the death of an old fiat system.

In complete contrast gold also operates as money under the completely opposite circumstances, when all is well; so well that there is indeed enough to go round.

The available evidence suggests that gold will often be adopted as money by the richest trading cultures (or occasionally international plunderers) of any given era.

When the Ionians were the commercial powerhouse of the eastern Mediterranean gold became their currency - taking over from iron. The same happened for the Athenians. It occurred again for the Romans in the first millennium, for the Venetians at the start of the renaissance, for the Spanish in the 16th century, for Britain in the 19th century, and in America through until 1933. In every case, except the Spanish who simply grabbed the stuff, these societies enjoyed a substantial and prolonged trade surplus. (Though to be fair to the Spanish some of the historical rules about trade were not so very different from the Spanish style gold-grab.)

Gold was how they balanced the books. It was simply the easiest thing to acquire and bring home from their foreign adventures - whether military or commercial - and it was a convenient way of avoiding a risky accumulation of foreign wealth.

This is not mandated by some monetary rulebook which says that gold shall balance the books, it just happens to be very convenient because gold is compact, scarce, easily recognized, not subject to variations in composition in different countries, consistently retains international purchasing power, and once refined has no technological, legal/administrative, or labour component as part of its value. It is an ideal medium for repatriating foreign earnings.

Traders and adventurers bringing home gold start shopping with bullion. They may even coin gold themselves, and the associated prestige has often been sought by whomever controls the state's money. Where gold is the unit of money in use by the rich - and it is in sufficient supply - there is no obvious reason why a central bank should not take to issuing gold coinage or gold backed notes itself. And that is precisely what has frequently happened.

But it is never a phenomenon which is available everywhere at once, only, in fact, to one or two strong trading countries in the world at any given time, and then temporarily. The accumulated wealth undermines the productive energies of its creators. Their domestic producers start to concentrate on supplying things which poorer countries neither want nor can afford, and the bullion inflow stalls. As that trading strength diminishes over time the power of Gresham's law dominates, and gold circulation diminishes irreversibly - as the great Winston Churchill found out when he tried to return Britain to the gold standard in 1925.

Gold based money - even for economic superpowers - is temporary. It disappears from circulation and seeks out the next great producers - to whom it will generally gravitate in settlement of new international trading debts.

Curiously the strongest industrial exporting nations of the last 50 years (notably Japan and Germany) have chosen to accumulate US dollars rather than gold, and now, instead of possessing bullion within their own borders these great exporters now own substantial slices - apparently some 40% - of the capital stock of foreign countries (particularly the United States) which buy their exports.

This is a break with ordinary patterns of international trade. It indicates that Germany and Japan are trusting the people of the USA to defend foreigners' property rights over American self-interest.

Meanwhile it explains - in part - the relative availability of gold and its low price by previous standards. It also raises the question of the attitude towards dollars (and gold) by the next generation of exporting powerhouses.

There is evidence that the Arabian oil exporters show a growing appetite for gold, with Dubai having comfortably the largest per capita gold inventory in the world, and Saudi Arabia having a reducing tolerance for dollars. Equally interesting is a growing Chinese demand. After a prolonged abolition of private gold ownership, and co-incident with its growing status as a world exporter, China has recently created its Shanghai Gold Exchange and is extending the right to private gold ownership to individuals. It would be wrong to assume that this presages a common use of gold as money within China, but its use within the trading elite of Chinese society is certainly consistent with previous episodes.