Olmec Iron

The Book of Mormon mentions iron in a mineralogical context five times:
2 Nephi 5:15 work in all mannner of iron, copper, brass, steel, gold, silver, precious ores ca. 590 BC
Notice the verb is "work" which does not necessarily imply a smelter or blast furnace.
Jarom 1:8 exceedingly rich in gold, silver, precious things, iron, copper, brass, steel ca. 400 BC

Mosiah 11:3, 8 gold, silver, ziff, copper, brass, iron, precious things ca. 150 BC
Ether 10:23 work in all manner of ore, gold, silver, iron, brass, copper ca. 1,100 BC
Notice the extractive process. The Jaredites dug ores out of the earth and then worked the ores. As in the 2 Nephi example, this does not necessarily imply a smelter or metallurgical furnace.

Iron is implied when steel is mentioned in an extractive mineralogical context in Jaredite times:
Ether 7:9 molten out of the hill, and made swords out of steel ca. 2,000 BC. The wording here could refer to a hammering, heating, quenching, and re-heating process to forge tempered steel out of naturally-occurring high grade iron ore.

Steel is carburized or quenched and tempered iron. Iron was known anciently from meteoric sources. King Tut's famous "steel" dagger on display in the Cairo Museum was pounded from meteoric iron.

Steel Dagger from King Tut's Tomb ca. 1323 BC
Photo by Daniela Cornelli

Meteoric iron is rare on the surface of the earth. High grade iron ores such as hematite and magnetite are much more abundant and are mined commercially today. We have known about polished Olmec hematite mirrors for decades.

Olmec Polished Hematite Mirror from Guerrero
Photo by Linda Schele

This is a similar example.

Olmec Polished Hematite Mirror from Guerrero
Photo by Linda Schele

Both mirrors are dated prior to 400 BC, the traditional date associated with the Olmec collapse.

We also know that another form of iron ore, ilmenite (a principal modern source of titanium), was worked at industrial scale at the first Olmec capital, San Lorenzo. Ann Cyphers Guillén found 8 tons of it at a workshop in the SE sector of the San Lorenzo plateau.

Perforated, Polished Ilmenite Artifacts from San Lorenzo
Photo by Ann Cyphers Guillén

This photo is in Ann Cyphers Guillén, "San Lorenzo Tenochtitlán," in Los Olmecas en Mesoamérica, edited by John E. Clark, (Mexico City: Citibank/Mexico, 1994). The ilmenite  was imported from Chiapas and Oaxaca. Similar concentrations of worked ilmenite pieces were found in Plumajillo and Amatal, Chiapas.

Sites with Worked Ilmenite Iron Ore

The perforations were made with a drill, likely using fine sand as an abrasive. The San Lorenzo workshop dates from ca. 1,100 BC. Several of the San Lorenzo artifacts were analyzed by BYU geologists. The report is Steven E. Jones, Samuel T. Jones, and David E. Jones, "Archaeometry Applied to Olmec Iron-Ore Beads," BYU Studies 37:4 (1997-98).  The iron artifacts could have been used as jewelry, currency, chain mail armor, or miniature tools (a typical bead is 3 centimeters long) if fitted with a small wooden haft. They also could have served as weights for fishing nets. 

The Olmec mirrors and beads were pounded and "worked" from naturally-occurring high grade iron ore. They were not smelted in a metallurgical furnace. This is precisely the low tech process the Book of Mormon describes.

Matt Roper sent me this little gem. This is a polished hematite sculpture from the middle pre-classic (ca. 800 BC) in the Wadsworth Atheneum Museum of Art in Hartford, CT.

Olmec Seated Dwarf

An image of the piece was first published in 1943. It is the only known Olmec sculpture fashioned from iron.