Smelting of metal ores requires carbon and high temperature to produce molten metal. Traditional smelting used charcoal, a carbon product made from widely available wood. Unsurprisingly, therefore, charcoal was used widely for smelting in the early days of mining in the American West, because transportation was primitive while scrub vegetation and forests were abundant.

Because of this charcoal manufacture became widespread. Typically beehive-shaped kilns, or ovens, made of local stone were used. The kilns were charged with raw wood, which could include scrub and slash that otherwise were useless. The charge was allowed to smolder for about a month, after which the kiln was allowed to cool and then carefully opened. The finished charcoal could then be loaded.…