Martin Thomas Lamb claims that the Book of Mormon's references to iron and steel in the New World are anachronisms.
M. T. Lamb, The Golden Bible; or, the Book of Mormon: Is it from God? (New York: Ward & Drummond, 1887), 300-2
A. Iron, Steel and Brass.
The Book of Mormon tells us that Iron, Steel and Brass were in common use among the ancient Nephites as they are used to day:
. . .
Against these fictitious words the authorities are positive and numerous. Of the ancient inhabitants of Peru Mr. Baldwin says (Anc. Am., p. 248):
"They had great skill in the art of working metals, especially gold and silver. Besides these precious metals they had copper, tin, lead and quicksilver. Iron was unknown to them in the time of the Incas."
Mr. Squier says (Peru, page 469):
"The Indians had neither iron nor steel."
Of the inhabitants of Central America Mr. Bancroft says (Native Races, vol. 2, page 407):
"As I have already stated, none of these nations were acquainted with the use of iron in any shape."
Of the ruins of one of the most ancient cities in Central America (Copan) the same author says (Vol. 4, page 102):
"That iron and steel were not used for cutting implements is clearly proved by the fact that hard finity spots in the soft stone of the statues are left uncut in some instances where they interfered with the details of the sculpture."
Of Yucatan proper, the home of the Mayas, he says (Vol. 2, page 751):
"But the fact remains that stone implements with a few, probably of hardened copper, sufficed with native skills and patience for all purposes."
Sticks tipped with copper were used for plows (Vol. 2, page 475). Maya sculpture was executed with tools of stone. Vol. 4, page 278.