Mohs scale of mineral hardness Mohs scale of mineral hardness The Mohs scale of mineral hardness is a qualitative ordinal scale characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. Created in 1812 by German geologist and mineralogist Friedrich Mohs, it is one of several definitions of hardness in materials science, some of which are more quantitative. The method of comparing hardness by seeing which minerals can visibly scratch others is, however, of great antiquity, having been mentioned by Theophrastus in his treatise "On Stones", c. 300 BC, followed by Pliny the Elder in his "Naturalis Historia", c.
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