The vapman classic features a thin layer of mica [a naturally occurring mineral] that protects the wood from charring. Mica is natural and harmless; it serves as a heat reflector and further increases vapman's legendary efficiency. However, this heat protection is primarily an aesthetic advantage, as the pure is in (almost) no way inferior to the classic in function.
On the pure the beautiful, bare wood will form a thin carbon layer through use. It will then be this carbon layer to provide thermal insulation to your vapman. In normal use and with a standart flame lengh (1-1.5cm), the charring process wont be initiated because of the chimney effect - it only chars when the wooden heat shield is burned directly.