Rockwell scale Rockwell scale The Rockwell scale is a hardness scale based on indentation hardness of a material. The Rockwell test determines the hardness by measuring the depth of penetration of an indenter under a large load compared to the penetration made by a preload. There are different scales, denoted by a single letter, that use different loads or indenters. The result is a dimensionless number noted as HRA, HRB, HRC, etc., where the last letter is the respective Rockwell scale (see below). When testing metals, indentation hardness correlates linearly with tensile strength. This important relation permits economically important nondestructive testing of
95-99 George Street, The Rocks aesthetically significant for containing some of the most intact Victorian period interiors for shops and residences in The Rocks area, including internal linings, joinery, some door and window furniture and an original plan form. 95-99 George Street makes an important contribution to the streetscape of George St, and is of significance in continuing the uniform character of the small scale retail shop buildings found in The Rocks. The building is aesthetically significant for its contribution to the streetscape of Greenway Lane, one of the pedestrian laneways in The Rocks area which are highly significant as evocation of the colonial townscape.