First, it’s necessary to decide how you want to deal with these precious metals. (I’m adding silver into the discussion, though other metals, like platinum and copper, are also significant.) People have been using them for coinage and ornamental purposes for thousands of years; early civilizations like the Sumerians and Egyptians seem to have focused primarily on gold for jewelry and ornamentation.
Weighing your choices
Gold is measured by troy ounces (12 troy ounces to a pound). It’s extremely heavy for its volume; ‘specific gravity’ gives it a weight more than 19 times heavier than water. (Gold-panning miners rely on this, looking for gold in river bottoms, where it would sink and become lodged in crevices.)