Which one among the following elements is known to be discovered the earliest?

Gold is considered one of the earliest known elements, discovered around 6000 BCE or earlier. Its natural occurrence in pure metallic form (nuggets) and distinctive yellow color made it easy for ancient humans to find and use. Copper was discovered around 9000 BCE in some accounts but gold artifacts predate systematic copper use in many cultures. However, in the context of this question and standard references, gold is typically cited as the earliest discovered element. Oxygen was discovered in 1774 by Priestley, and uranium in 1789 by Klaproth.