Properties of gold Most metallic artefacts recovered by archaeologists are fashioned from either gold or silver, which are thought to be the first metals to be worked by humans. They are both relatively easy to reclaim from the rocks in which they’re found, and are easy to work. Gold is extremely unreactive and doesn’t tarnish like most other metals. Consequently, gold jewellery can survive essentially unchanged for thousands of years. Gold is also extremely heavy, with a density of 19.4 g cm-3. The density of lead, by comparison, is only 11.4 g cm-3. Its heaviness plays a crucial part in many of the physical methods used to extract gold from its various sources.