Mohs scale of mineral hardness 77 AD. While greatly facilitating the identification of minerals in the field, the Mohs scale does not show how well hard materials perform in an industrial setting. Despite its lack of precision, the Mohs scale is highly relevant for field geologists, who use the scale to roughly identify minerals using scratch kits. The Mohs scale hardness of minerals can be commonly found in reference sheets. Mohs hardness is useful in milling. It allows assessment of which kind of mill will best reduce a given product whose hardness is known. The scale is also in use at digital electronic manufacturers, for
145 George Street, The Rocks group as a whole, contributes to a precinct unique to NSW with its historic associations and streetscape character. The group is an important part of The Rocks Heritage Conservation Area being sympathetic in scale and character and an extension of the remaining earlier buildings of George St, presenting a unified streetscape. The buildings are tangible evidence of the redevelopment of The Rocks in the last decade of the 19th century and first decade of the 20th century. 145 George Street has high social significance as a contributory element associated with the historic character of The Rocks, which is held in