BullRunner, following the Market

DeepWealth: "In fact, the properties required of money were first described by Aristotle in the fourth century BCE.
It is durable. It won't evaporate, mildew, rust, crumble, break, or rot. Gold, more than any other solid element, is chemically inert. This is why foodstuffs, oil or artwork can't be used as money.

It is divisible. One ounce of gold-whether bullion, coin, or dust-is worth exactly 1/100th of one hundred ounces. When a diamond is split, its value may be destroyed. You can't make change for a piece of land.

It is convenient. Gold allows its owner physically to carry the wealth of a lifetime with him. Real estate stays where it is. An equivalent value of copper, lead, zinc, silver, and most other metals would be too heavy.

It is consistent. Only one grade exists for 24-carat gold, so there is no danger of owning 24-carat gold varying in quality. Twenty-four-carat gold (pure gold) is the same in every time and place since gold is a natural element, unlike gems, artwork, land, grain, or other commodities.

It has intrinsic value. Gold finds new industrial uses each year. Of all the metals, it is the most malleable (able to be hammered into sheets less than 5-millionths of an inch thick), most ductile (a single ounce can be drawn into a wire 35 miles long), and the least reactive (it can stand indefinite immersion in seawater, does not tarnish in air, and can withstand almost any acid). Next to silver, it's the most conductive of heat and electricity and the most reflective of light.
One important last point was not listed by Aristotle, probably only because he lived before the creation of paper and banking.
Gold cannot be created by government. Gold can, of course, be debased with impurities or falsified in weight, and governments strapped for revenue have tried those tricks. "