Metals of antiquity
The phrase "metals of antiquity" refers to seven metals which humankind 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. Of all the elemental metals that are now known (86, as of 2007[update]), only these seven were known up until the 13th century, when arsenic was first isolated.
The metals of antiquity generally have low melting points, with iron being the obvious exception.
- Mercury is liquid at STP
- Tin melts at 231°C
- Lead melts at 328°C
- Silver at 961°C
- Gold at at 1063°C
- Copper at 1083°C
- Iron is the outlier at 1538°C, making it essentially impossible to melt in antiquity.
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 CO at 900°C
- Copper and lead can be roasted to produce the oxides, then reduced with CO at 900°C
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.
- "History of Metals".
- Nick Kollerstrom. "The Metal-Planet Affinities - The Sevenfold Pattern". Retrieved 2011-02-17.
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