Indentation hardness test, performed with either 3 gf or 9 gf loads, preceded the development of microhardness testers using traditional indenters. In 1925, Smith and Sandland of the UK developed an indentation test that employed a square-based pyramidal indenter made from diamond. They chose the pyramidal shape with an angle of 136° between opposite faces in order to obtain hardness numbers that would be as close as possible to Brinell hardness numbers for the specimen. The Vickers test has a great advantage of using one hardness scale to test all materials.The first reference to the Vickers indenter with low loads was made
Lilyvale, The Rocks majority of external render was removed and the brick walls painted. As at 30 March 2011, "Lilyvale" 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. "Lilyvale" Cottage is a very fine and rare example of Colonial Regency freestanding domestic architecture in the city centre. It is in good condition, having been conserved in 1987 by SCRA, and retains much of its early form and materials. The cottage