Metals of antiquity

The metals of antiquity are the seven metals which humans had identified and found use for in prehistoric times: gold, silver, copper, tin, lead, iron, and mercury. These seven are the metals from which the modern world was forged; until the discovery of arsenic (now classified as a metalloid) in the 13th century, these were the only known elemental metals, compared to the 91 known today.
Characteristics.
Melting point.
The metals of antiquity generally have low melting points, with iron being the exception.
Extraction.
While all the metals of antiquity but tin and lead occur natively, only gold and silver are commonly found as the native metal. 
Rarity.
While widely known during antiquity, most of these metals are by no means common.
Yet all were known and available in tangible quantities in ancient times. 
Additionally, despite being approximately 1,000 times more abundant in the crust than the next most abundant ancient metal, iron was the last to become available due to its melting point (see above), including requiring tools made from alloys such as bronze to work in quantity. Other comparably abundant elements, such as titanium (approximately 4,400ppm) and aluminium (approximately 83,000ppm), were not available until the modern era. This was due almost entirely to the huge quantities of energy required to purify ores of these elements. Energy requirements and tool availability were, therefore, the primary limiting factors affecting an ancient civilisation's ability to access metals, rather than those metals' relative abundances.
Symbolism.
The practise of alchemy in the Western world, based on a Hellenistic and Babylonian approach to planetary astronomy, often ascribed a symbolic association between the seven then-known celestial bodies and the metals known to the Greeks and Babylonians during antiquity. Additionally, some alchemists and astrologers believed there was an association, sometimes called a rulership, between days of the week, the alchemical metals, and the planets that were said to hold "dominion" over them.