Anyone who has sat around a campfire or witnessed a forest fire knows that wood burns. But they are also aware that wood generates a great deal of smoke as it burns. This is a result of the incomplete combustion of the oils and resin in the wood, along with the high moisture content. Unfortunately, this limits the practicality of wood as a fuel for a variety of purposes including indoor cooking and the smelting of metals. In the latter case, the impurities in the wood smoke result in a lower grade of ore being obtained.

It was for the purposes of smelting copper and subsequently iron that charcoal was first used. Its origin is unknown but it has been used in Europe for over 5,500 years. It was the smelting fuel for the bronze and iron ages of civilization, being used in smelters and the blacksmith's shop.

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