A method for placing an optical lens, with a first side and a second side, on a block piece for holding the optical lens and which has a coupling part for holding the block piece in a workpiece chuck and with a holding part for fastening the lens. The holding part has a convex or concave holding surface corresponding to a first side of the lens. The holding surface is, according to the shape of the lens to be held, provided in the form of a negative free-forming surface, and the block piece is made from a plastic that can be machined.