In John Dehlin’s essay on Archaeology and the Book of Mormon he writes:
Although the Book of Mormon twice mentions that Nephi moltened steel out of a rock, only crude iron technology existed in 600 BC. Steel did not yet exist, as it required charcoal heated to 2,500-3,000 degrees. Charcoal wasn’t discovered until some 1,500 years later and required the laborious felling of acres of trees to create sufficient charcoal.“Archaeology and the Book of Mormon,” Mormon Stories, accessed March 11, 2019.
The claim that steel was unknown in Nephi’s day is uninformed and erroneous.
The process of making ancient steel has been described by various authorities of on the subject.
Phillip King and Lawrence Stager explain:
Wrought iron heated in contact with charcoal (carbon) at high temperature produces carbonized iron or steel, which is more malleable than cast iron. Steel can be hardened by quenching (practiced as early as the tenth century BCE), that is, cooling off the red hot steel by sudden immersion into a vat of cold liquid.1
James Muhly, who is a leading authority on the subject of ancient metallurgy has written:
The addition of carbon, absorbed into the surface of the iron by a sort of osmosis while the hot iron was in contact with charcoal for an extended period in a reducing atmosphere, greatly increased the hardness of the metal. Such iron, with up to 0.8 percent carbon, is known as steel. If this red hot steel was quenched, by plunging it into a bath of cold water, the resulting product was harder than any bronze. The quenching produced a layer of very hard martensite on the surface of the iron, the amount of martensite formed dependent upon the thickness of the object in question (and thus the rate of cooling). If too much martensite was produced, the resulting steel would be very hard but also very brittle and liable to shatter. It was then necessary to reheat the object in an oxidizing atmosphere, in order to relieve the strains from the freshly formed martensite, a process known as tempering. Tempering was actually a trade-off, sacrificing hardness for greater durability and toughness . . . In the twelfth century BCE, all the necessary technology for producing effective tools, implements and weapons of quenched and tempered steel was developed in surprisingly short order.2
Archaeologists have recovered steel artifacts from various sites in the ancient Near East dating to before Nephi’s day:
Steel artifacts from the Iron IA (twelfth century) burial cave in the Beqa Valley, Jordan, provide an interesting body of material in that steel was used there to produce bracelets and rings. 3
According to Anthony Snodgrass:
Egyptian axes and other implements dating from about 900 B.C. onward were found to have been carburized, quenched, and probably tempered as well, a finding that is quite incompatible with the picture of backwardness and isolation that is sometimes painted.4
Recently Naama Yahalom-Mack and Adi Eliyahu-Behar reported that over sixty badly corroded iron objects were recovered by archaeologists from sites in Syro-Palestine dating from the late second and early first millennium B.C. These included knives, tools, weapons, and bracelets. Chemical analysis was done on each of these. They report:
The results showed that ‘ghost structures’ of pearlite, clearly indicating the presence of carbon, were present in almost all the objects (excluding three), demonstrating that almost all were made of steel.5
Contrary to John Dehlin’s claims, the process of making iron into steel tools and other useful objects was known in the ancient Near East, including the land of Israel the land from which Nephi came hundreds years before Lehi left Jerusalem. The idea that Nephi could have known or learned how to make steel tools out of iron ore poses no problem for the Book of Mormon, but is consistent with what is now known and what we continue to learn about the ancient world.