+- RomanArmyTalk (https://www.romanarmytalk.com/rat)
+-- Forum: Research Arena (https://www.romanarmytalk.com/rat/forumdisplay.php?fid=4)
+--- Forum: Roman Military History & Archaeology (https://www.romanarmytalk.com/rat/forumdisplay.php?fid=8)
+--- Thread: Iron Pot Hole Fix (/showthread.php?tid=31100)
Iron Pot Hole Fix - Lothia - 05-17-2019
Ave Civitas,
Read an interesting article from the Ancient Origins Web site concerning road repair in the city of Pompeii.
https://www.ancient-origins.net/news-history-archaeology/roman-roads-0011920
Tom
RE: Iron Pot Hole Fix - Crispianus - 05-18-2019
(05-17-2019, 01:41 PM)Lothia Wrote: Ave Civitas,
Read an interesting article from the Ancient Origins Web site concerning road repair in the city of Pompeii.
https://www.ancient-origins.net/news-history-archaeology/roman-roads-0011920
Tom
Could be native iron (or high ferric content) occuring as inclusions in the Volcanic rock used for the road surface, I guess we'll find out when its analysed:
Romans May Have Repaired Roads with Molten Iron
RE: Iron Pot Hole Fix - Dan Howard - 05-18-2019
The roads would have been repaired using slag from the iron bloomery, not the iron itself. Their "iron droplets, spatters, and stains" would be indistinguishable from the iron remnants in bloomery slag. Smelters were only 80-90% efficient so 10-20% of the iron was still in the slag after the smelt.
Roman iron production resulted in millions of tons of slag byproduct and they were constantly trying to find ways to dispose of it. Adding it to road-base seems like a pretty good use to me.
RE: Iron Pot Hole Fix - Dan Howard - 10-22-2019
Quote:Smelters were only 80-90% efficient so 10-20% of the iron was still in the slag after the smelt.
I was queried on this so wanted to clarify. This doesn't mean that 10-20% of the slag content is iron. It means that 10-20% of the original iron content still remains after the smelt. It depends on the quality of the ore. If the ore contains 30% iron and the smelter is 90% efficient then the resultant slag will consist of 3% iron.* This is the "iron droplets, spatters, and stains" that the observers found in the road. The author of the above article should have consulted an archaeo-metallurgist before writing that nonsense about molten iron.
* 30% x 10% (100-90) = 3%
RE: Iron Pot Hole Fix - Gunthamund Hasding - 10-27-2019
well this is a supposition, on the other side we have to keep in mind that in Pompeii quite a lot of temperature was present when the pyroclastic clod reached the city so might be that parts of that iron could have melted and mixed with stone, not sure if chemical analysis were done or only physical observations
RE: Iron Pot Hole Fix - Dan Howard - 10-27-2019
Iron melts at over 1500 deg C. Pyroclastic lava flows rarely exceed 1200 deg C. Pompeii was buried in tephra ash, not lava, which has an even lower temperature. Analysis reckons that there was nothing over 300 deg C in the city and nothing over 350 deg C on the outskirts. Based on the available data, it is irrational to conclude that the Vesuvius eruption could have melted iron in Pompeii.
We still use smelter slag for road base today. The only difference is that modern smelters are far more efficient so the resultant slag contains negligible amounts of iron.
RE: Iron Pot Hole Fix - Gunthamund Hasding - 10-31-2019
yeah you are right I thought that there were some reports with larger than 1500o C in some places but probably was closer to the volcano, although the slag would have cooled pretty fast I suppose.