That's not true at all. Aside from it's use in jewelry, gold is used in electronics and industrial chemistry. It actually has industrial uses, thus there is a certain floor on it's value.

However, that floor (due to industrial/etc uses) is probably in the neighborhood of $10-$20 per Oz, or completely decoupled from the actual price at any given time in written history.

It has some 'worth' as it is useful for making nice jewelry and is a good conductor too.