Marble common 10000 to 8992 -- 9405 Stone hard ---- to 8594 -- 9130 Gres ---- to 8286 -- 8990 Lead ---- to 7604 -- 5555 Tin ---- to 7143 -- 6792 Stone calcareous soft ---- to 6792 -- 7281 Clay ---- to 6400 -- 6286 Antimony ---- to 6286 -- 6792 Oker ---- to 5400 -- 5571 Gypsum ---- to 4920 -- 5116 Wood ---- to 2200 -- 2857