Stone sculpture stone carving. Alabaster and softer kinds of serpentine, all about 3 on the Mohs scale, are more durable than soapstone. Alabaster, in particular, has long been cherished for its translucence. Limestone and sandstone, at about 4 on the Mohs scale, are the only sedimentary stones commonly carved. Limestone comes in a popular oolitic variety, about twice as hard as alabaster, that is excellent for carving. The harder serpentines can also reach 4 on the Mohs scale. Marble, travertine, and onyx are at about 6 on the Mohs scale. Marble has been the preferred stone for sculptors in the European tradition
Oamaru stone In Oamaru itself the stone is most commonly found as the primary construction material, with many of the town's more notable buildings (such as the Waitaki District Council building) showing its distinctive creamy colour. Its ease of working also appeals to sculptors and examples of Oamaru stone sculpture can be found throughout New Zealand. The source of the stone is a 40-metre thick deposit inland from Oamaru consisting of bryozoan limestone. Oamaru stone is limestone with a uniform granular creamy white consistency and colour. Predominantly (90%) calcium carbonate, trace chemicals within it include alumina (1.5%), iron oxide (0.5%) and silica