Metals of antiquity

The metals of antiquity are the seven metals which mankind had identified and found use for in prehistoric times. These elements, gold, silver, copper, tin, lead, iron, and mercury, are the metals from which our modern world was forged. Until the discovery of arsenic in the 13th century, these were the only elemental metals known to man, compared to the 91 known today.

Characteristics

Melting point

The metals of antiquity generally have low melting points, with iron being the obvious exception.

• Mercury melts at −38.829 °C
• Tin melts at 231 °C
• Lead melts at 328 °C
• Silver at 961 °C
• Gold at 1063 °C
• Copper at 1083 °C
• Iron is the outlier at 1538 °C, making it essentially impossible to melt in antiquity.

Extraction

While it is true that all but tin and lead do occur natively, only gold and silver are by any means commonly found as the native metal. However, no temperature higher than 900 °C (easily reachable with charcoal and bellows) was required to extract these metals from their ores.

• Gold and silver occur frequently in their native form
• Mercury compounds are reduced to elemental mercury by simple heat (500 °C).
• Tin and iron occur as oxides and can be reduced with carbon monoxide (produced by, for example, burning charcoal) at 900 °C.
• Copper and lead can be roasted to produce the oxides, then reduced with carbon monoxide at 900 °C.

Rarity

While widely known during antiquity, these metals are by no means common. Of the 78 elements occurring naturally in the earth's crust, with oxygen and silicon being the first two:

• Iron is the 4th (4.1% by mass)
• Copper is next at 26th (50ppm)
• Lead is 37th (14ppm)
• Tin is 49th (2.2ppm)
• Silver is 65th (70ppb)
• Mercury is 66th (50ppb)
• Gold is the 72nd (1.1ppb)

Yet all were known and available in tangible quantities in ancient times.

See also

• Timeline of chemical element discoveries