A method of providing datum features on a ceramic article including the steps of providing a ceramic member having a plurality of substantially parallel holes extending into the ceramic member. Providing a plurality of tubular mounts, the cross-sectional area of each tubular mount being less than the cross-sectional area of the corresponding hole. Applying adhesive to the exterior surface of each one of the tubular mounts and inserting an adhesive covered tubular mount into each one of the holes. Providing a fixture member having a plurality of substantially parallel projections extending from predetermined positions. Positioning the ceramic member on the fixture member such that each projection locates in one of the tubular mounts and fixes the tubular mounts at the predetermined positions. The ceramic article may be removed from the fixture member or located in a machine tool using the fixture member and machining the ceramic article.