African Blackwood is one of the woods that looks so well after itself, it is simply saturated with oils, pieces that have been lying outside in my yard for 5 years and longer still gets oil bubbling on its surface if I work to hard or with a blunt tool where the friction is high. I honestly think one would never have to treat these brushes to preserve them, simply keep them away from severe conditions, I cannot see any treatment replacing its own oils, and a coating would be purely cosmetic. This guy has bark, sapwood and hardwood, but make no mistake this sapwood is very dense and heavy, unlike must other trees It weighs a chunky 100 grams, measures 125 mm tall, with the loft set at 65 mm. It is fitted with a 28 mm Finest two band badger knot. a Piece of bushveld in your bathroom.