Hardwood charcoal

Description

The resulting soft, brittle, lightweight, black, porous material resembles coal.[1] Note that the current trade nomenclature for charcoal is "lump charcoal" and that products sold as "charcoal briquettes" are made from a mix of materials, such as lowgrade coal, sawdust, wax, and starch binders, and often do not contain any true charcoal.

Production methods
Charcoal has been made by various methods. The traditional method in Britain used a clamp. This is essentially a pile of wooden logs (e.g. seasoned oak) leaning against a chimney (logs are placed in a circle). The chimney consists of 4 wooden stakes held up by some rope. The logs are completely covered with soil and straw allowing no air to enter. It has to be lit by introducing some burning fuel into the chimney; the logs burn very slowly (cold fire) and transform into charcoal in a period of 5 days\' burning. If the soil covering gets torn (cracked) by the fire, additional soil is placed on the cracks. Once the burn is complete, the chimney is plugged to prevent air from entering.[3]
Modern methods use a sealed metal container, as this does not have to be watched lest fire break through the covering.[citation needed] However onsite attendance is required. This is often carried out by the last forestry workers to live in working woodland in the western world. There has been a resurgence of this particuarly in the UK. A good example of this is Bulworthy Project where charcoal production supports an experiment in lowimpact living and nature conservation

    Lump charcoal is made directly from hardwood material and usually produces far less ash than briquettes.