Mohs scale of mineral hardness integrity, they are not considered "scratches" for the determination of a Mohs scale number. The Mohs scale is a purely ordinal scale. For example, corundum (9) is twice as hard as topaz (8), but diamond (10) is four times as hard as corundum. The table below shows the comparison with the absolute hardness measured by a sclerometer, with pictorial examples. On the Mohs scale, a streak plate (unglazed porcelain) has a hardness of approximately 7.0. Using these ordinary materials of known hardness can be a simple way to approximate the position of a mineral on the scale. The table below
Shore durometer Shore durometer The Shore durometer is a device for measuring the hardness of a material, typically of polymers, elastomers, and rubbers.. Higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. Lower numbers indicate less resistance and softer materials. The term is also used to describe a material‘s rating on the scale, as in an object having a “‘Shore durometer’ of 90.” The scale was defined by Albert Ferdinand Shore, who developed a suitable device to measure hardness in the 1920s. It was neither the first hardness tester nor the first to be called a