Since the 14th Century, gold’s purchasing power has maintained a broadly constant level. To put this in practical terms, an ounce of gold has repeatedly bought a mid-range outfit of clothing. This was true in the fourteenth century, when an ounce of gold was worth £1.25 to £1.33; it was true in the late 18th century and it remained true at the beginning of this century (2000 to 2008), when an ounce of gold averaged £269 or $472. Even the exchange rate between gold and commodities has been relatively constant over the centuries.
On the other hand, the US dollar that bought 14.5 loaves of bread in 1900 buys only 3/4 of a loaf today. While inflation and other forces have ravaged the value of the world’s currencies, gold has emerged with its capacity for wealth preservation firmly intact. Being no-one’s liability, gold exhibits the same wealth preserving qualities in the face of financial turmoil, earning a reputation as a crisis hedge in addition to its credentials as an inflation hedge.
Taken from Gold.org