Rosiwal scale with corundum with a base value of 1000. The Rosiwal scale is used in mineralogy in the same way as Mohs scale and Knoop scale. Rosiwal scale The Rosiwal scale is a hardness scale, with its name given in memory of the Austrian geologist August Karl Rosiwal. The Rosiwal scale bases its measure on absolute values, unlike the Mohs scale whose values are relative values, its interest is relegated to the amateur or an approach that makes it useful in the research field ('in situ'). The Rosiwal method (also called Delesse and Rosiwal) is basically a method of petrographic analysis
Indentation hardness have an effect on the hardness measurement, as long as the indentation is large compared to the surface roughness. This proves to be useful when measuring the hardness of practical surfaces. It also is helpful when leaving a shallow indentation, because a finely etched indenter leaves a much easier to read indentation than a smooth indenter. The indentation that is left after the indenter and load are removed is known to "recover", or spring back slightly. This effect is properly known as "shallowing". For spherical indenters the indentation is known to stay symmetrical and spherical, but with a larger radius.