Gold is the most ductile and malleable of all metals.  One ounce can be stretched into a wire five miles long or hammered into a sheet thin enough to cover 100 square feet.

Two-thirds of the world’s gold supply comes from a 300-mile semicircle running east-west from Johannesburg, South Africa.

If all the gold mined over the last 6,000 years were collected and melted down, it would fill no more than 30 large railroad boxcars.  Or it would make a 3 3/4-foot-thick slab as large as a football field.  Or it would form a cube with 19-yard-long sides.

Almost all the gold mined, about 95,000 metric tons, is still in man’s possession.  It is estimated that another 34,000 metric tons remains in the earth today.

Alchemists in Greece and Alexandria were trying to transform lead into gold in 300 BC.  No one has ever succeeded.

The word karat (and carat, the unit of weight used to measure gems) derives from the Arabic qirat, meaning bean or pod, or the Greek keration, meaning carob bean.  The small seeds of the carob tree were once used to balance the scales in weighing gems and gold in Oriental bazaars.

Gold can be made into a film 5 millionths of an inch thick, which is applied to glass and used in some office buildings.  Ordinary glass is an inefficient heat shield, but glass coated with gold will reflect up to 90% of the sun’s heat.