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
Lilyvale, The Rocks is an integral component of a group of 19th century houses in this section of Cumberland Street, which evokes a traditional Rocks streetscape. "Lilyvale" (176 Cumberland Street), the Butchery Building (178-180 Cumberland Street) & Hart's Building (10-14 Essex Street) as a group: The surviving buildings occupying the block bounded by Cumberland, Essex and Gloucester Streets, south of the Cahill Expressway, collectively illustrate the range and diversity of small scale development in this area of The Rocks between 1840 and World War I. They combine with nearby precincts to the south of Essex Street to extend that diversity into the early