Abstract: Gemstone working apparatus which includes a rotatable base, one or more two gemstone working members including a first gemstone working member which defines a first gemstone working surface adapted for removable mounting on the base; and a second gemstone working member which defines a second gemstone working surface, of a different grain size than that of the first gemstone working surface, adapted for removable mounting on the base concentrically with the first gemstone working member; and rotational height adjustment apparatus for adjustment of the height of the second gemstone working member by rotation thereof relative to the first gemstone working member to any non-predetermined rotational position, thereby to bring the second working surface into planar alignment with the first working surface so as to provide a combination abrasive surface of varying grain size and of uniform level.