Mohs scale of mineral hardness finding the hardest material that the given material can scratch, or the softest material that can scratch the given material. For example, if some material is scratched by apatite but not by fluorite, its hardness on the Mohs scale would fall between 4 and 5. "Scratching" a material for the purposes of the Mohs scale means creating non-elastic dislocations visible to the naked eye. Frequently, materials that are lower on the Mohs scale can create microscopic, non-elastic dislocations on materials that have a higher Mohs number. While these microscopic dislocations are permanent and sometimes detrimental to the harder material's structural
71 Harrington Street, The Rocks Iron. As at 27 April 2001, Archaeology Assessment Condition: Partly disturbed. Assessment Basis: Area under building only. Terraced into hill slope. As at 30 March 2011, this house and site are of State heritage significance for their historical and scientific cultural values. The site and building are also of State heritage significance for their contribution to The Rocks area which is of State Heritage significance in its own right. The site has historical significance as part of the Colony's hospital site in 1807, and the building as part of the 19th century housing stock in The Rocks. It has aesthetic