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
123-125 George Street, The Rocks Free Classical style, executed to give a sense of decorum to what would otherwise have been simple commercial / residential structures. The buildings have streetscape value as two buildings in a group of three that were designed to appear as one property. The buildings' scale and alignment to the street are typical of that found along the business precinct of George Street in The Rocks area. The street façades have remained relatively intact since they were constructed in 1882. The place has a strong or special association with a particular community or cultural group in New South Wales for social,