burr. Burr (or in the USA, burl) is the timber from the knotted roots or deformed branch of the tree, which when cut, displays the small circular knots in various gradations of colour. It is always cut into a decorative veneer, most commonly seen as burr walnut on 19th century furniture.
The buyers premium is an additional percentage charge on the hammer price of the item, imposed by the auction house to cover administrative costs. The buyers premium percentage varies between auction houses, with a range of 12.5% to 22%.