Tuesday, February 9, 2010

Ward Charcoal Ovens

Many years ago, I drove up Wildrose Canyon (Death Valley) and photographed the ten charcoal kilns. When I found out there are many sites like that in Nevada, I had to investigate. Well, it so happens the Ward Charcoal Ovens, the best-preserved ovens in Nevada, are just fifteen miles south of Ely, a place I head for every March. It turns out the six parabolic shaped ovens are just like the ones in Wildrose Canyon. Call them kilns or call them ovens they still do the same job. And as far as I’m concerned, they’re masonry masterpieces.

Parabolic is just a fancy way of saying beehive. Swiss-Italian masons called “Carbonari” built the Ward Charcoal Ovens in the late 1800’s. And that is why they look so good, he says with just a hint of Italian national pride.

Long before these ovens were built someone discovered that if wood is burned slowly in an oxygen-starved environment, the end result is charcoal. Place thirty-five cords of wood, in this case pinion and juniper pine which grew in abundance nearby, into each oven, heat the wood sufficiently for about twelve days, and the ovens will do their magic, which is called pyrolysis, the chemical decomposition of condensed organic substances by heating. I like calling it magic better. Vents located at the bottom of each oven were used to regulate the temperature inside. The beehive shape allowed heat to be reflected back onto the wood as it slowly cooked, thus making the whole process more efficient. The heat removes water from the wood, leaving behind blackish chunks...voila, charcoal.

What did they do with the charcoal? One way to separate silver from ore is to heat the ore with none other than, everyone say it together......charcoal. I wondered why charcoal, why not burn plain old wood? Well, it seems charcoal burns hotter and cleaner than wood and it heats the ore at just the right temperature. Smelting by this method is technically called pyrometallurgy and it happens to be the oldest extractive process.

These ovens were an important supplier to the various mines in the area. Eventually coke from coal was substituted for the charcoal, so the ovens closed somewhere around 1879. But new and more enterprising, and in some cases nefarious uses were devised for the ovens. They sheltered stockmen and prospectors during nasty weather and had the reputation as a hideout for stagecoach banditos. I’m happy to report I didn’t find any bandits hiding out the day I was there.

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