Chromium is a common addition to alloys to make materials like tool steel or stainless steel, and it’s long been thought to have been invented around the late 19th and early 20th centuries. But now, archaeologists have discovered that the ancient Persians were mixing chromium into their steel as far back as the 11th century – almost a thousand years earlier.

Using radiocarbon dating on several pieces of charcoal recovered from crucible and smithing slag from the site, the team dated the practice to between the 11th and 12th centuries. Scanning Electron Microscope imaging revealed traces of chromite, and in the crucible slag, they found steel particles containing between one and two percent chromium by weight.

That’s much less chromium than you’d find in modern stainless steel and tool steel, which can reach 11 to 13 percent, but the fact that it’s in something so old is significant.

“Our research provides the first evidence of the deliberate addition of a chromium mineral within steel production,” says Alipour, lead author of the study. “We believe this was a Persian phenomenon. This research not only delivers the earliest known evidence for the production of chromium steel dating back as early as the 11th century CE, but also provides a chemical tracer that could aid the identification of crucible steel artifacts in museums or archaeological collections back to their origin in Chahak, or the Chahak tradition.”

The team says that manuscripts from the time praised Chahak steel for its intricate patterns, but pointed out that swords made of the material were quite brittle. That’s consistent with its high phosphorus content, according to the study.

https://newatlas.com/materials/chromium-stainless-steel-ancient-persians-history/

PermeateFree said:

Chromium is a common addition to alloys to make materials like tool steel or stainless steel, and it’s long been thought to have been invented around the late 19th and early 20th centuries. But now, archaeologists have discovered that the ancient Persians were mixing chromium into their steel as far back as the 11th century – almost a thousand years earlier.

Using radiocarbon dating on several pieces of charcoal recovered from crucible and smithing slag from the site, the team dated the practice to between the 11th and 12th centuries. Scanning Electron Microscope imaging revealed traces of chromite, and in the crucible slag, they found steel particles containing between one and two percent chromium by weight.

That’s much less chromium than you’d find in modern stainless steel and tool steel, which can reach 11 to 13 percent, but the fact that it’s in something so old is significant.

“Our research provides the first evidence of the deliberate addition of a chromium mineral within steel production,” says Alipour, lead author of the study. “We believe this was a Persian phenomenon. This research not only delivers the earliest known evidence for the production of chromium steel dating back as early as the 11th century CE, but also provides a chemical tracer that could aid the identification of crucible steel artifacts in museums or archaeological collections back to their origin in Chahak, or the Chahak tradition.”

The team says that manuscripts from the time praised Chahak steel for its intricate patterns, but pointed out that swords made of the material were quite brittle. That’s consistent with its high phosphorus content, according to the study.

https://newatlas.com/materials/chromium-stainless-steel-ancient-persians-history/

That’s interesting in several ways.

roughbarked said:

PermeateFree said:

Chromium is a common addition to alloys to make materials like tool steel or stainless steel, and it’s long been thought to have been invented around the late 19th and early 20th centuries. But now, archaeologists have discovered that the ancient Persians were mixing chromium into their steel as far back as the 11th century – almost a thousand years earlier.

Using radiocarbon dating on several pieces of charcoal recovered from crucible and smithing slag from the site, the team dated the practice to between the 11th and 12th centuries. Scanning Electron Microscope imaging revealed traces of chromite, and in the crucible slag, they found steel particles containing between one and two percent chromium by weight.

That’s much less chromium than you’d find in modern stainless steel and tool steel, which can reach 11 to 13 percent, but the fact that it’s in something so old is significant.

“Our research provides the first evidence of the deliberate addition of a chromium mineral within steel production,” says Alipour, lead author of the study. “We believe this was a Persian phenomenon. This research not only delivers the earliest known evidence for the production of chromium steel dating back as early as the 11th century CE, but also provides a chemical tracer that could aid the identification of crucible steel artifacts in museums or archaeological collections back to their origin in Chahak, or the Chahak tradition.”

The team says that manuscripts from the time praised Chahak steel for its intricate patterns, but pointed out that swords made of the material were quite brittle. That’s consistent with its high phosphorus content, according to the study.

https://newatlas.com/materials/chromium-stainless-steel-ancient-persians-history/

That’s interesting in several ways.

Indeed. Another one of the lost arts. Lost for eight centuries or so.

It doesn’t seem so impossible back that early, because even more ancient knowledge of chemistry (from the early Egyptian period according to wiki) was advanced enough to know that manganese (the element next to chromium) added to glass removed the green tint caused by iron.