This is what happens when I try to be laconic
hence my usual Tolstoyean ramblings. What I actually meant was that the Tlingit were somewhat skilled metalworkers pre-contact, and that they had learned to work iron, having expounded on thier skills with copper. I did not mean that there were smelters and forges, nor were these areas any type of Native American 'Birmingham'.
My mention of Chinese and Siberians implied that the metalwork skills were learned from these peoples, which is not correct. I found more accurate detail in "The Tlingit Indians" by George Thornton Emmons, annotated by Frederica de Luna, 1991, pp.187-89);
"...while iron ore is found in Alaska, the natives had no means of reducing the ore to precious metal. It would seem that before the coming of trade vessels toward the close of the 18th century, the coast natives had already procured small bits of manufactured iron, either from wreckage or from inland southern trade from Mexico, and knew its use. From thier knowledge of copper they soon learned to work it into weapons, tools and ornaments, and almost invariably followed the original forms, as may be observed in thier manufactured spear heads, adzes, knives etc which are exact replicas of the stone implements".
Apparantly Emmons' work was published as paper #70 for the American Museum of Natural History at earlier date, and this reference is republished and annotated by DeLuna.
It would appear they did have charcoal as Emmons continues, "..in working steel and iron, they learned to soften it by heating it with charcoal, enabling them to work it more easily, and then bring the temper back by plunging it into a bath of oil and water".
It appears that iron nails, fittings etc. from wrecked ships' driftwood which was carried to these shores by the Japanese current had presented the opportunity to experience this metal to the natives, already well skilled in copperworking. Learning to work the metal gave them the basic knowledge which was expanded with the arrival of trade ships later in the 18th century. It has been suggested that ironworkers may have been among survivors of these wrecks which included Russian, Japanese, and even Spanish ships from as early as 1745.
I am always amazed at the vast distances covered in trade networking, which was well established far into prehistoric times, and how these kinds of primitive technology were passed to regions so remarkably faraway. While the Tlingit did not have the means to produce iron or steel, they did have the skills to develop working it quite well, which made iron one of the most desired commodities of trade sought by them.
All the best,