It is funny stuff Onyx. I have never really felt at home carving it. For one thing it does not carve very nicely like a marble or a limestone. It behaves more like glass than stone. It rings like glass too, when you hit it. The other thing to understand about onyx is the translucence. Marble will let a little light into it but not like Onyx. This means that ( I am beginning to work out) the sculptural approach needs to be radically different in order to compensate for these changes in material. Up to now I have not felt I have had much success. I am trying a similar carving to the walking figure and trying to make the approach suit the material. The surface is rough at the moment so the translucence does not really show.