From Ballarat and District Industrial Heritage Project
- From the beginning [of mining in Victoria] it appears that quartz was roasted before it was crushed and a description of this process appeared in March 1853 in a Melbourne periodical, The Australian Gold Diggers Monthly Magazine. The heating and quenching of quartz to render it brittle had been known from antiquity and is described by Agricola who says that roasting was common to all ores. Crushing methods at the time were primitive and anything which would make crushing easier was useful. The iron used in crushing machines was comparatively soft and roasting lessened the wear it suffered. Bendigo toll mills in 1854 treated roasted quartz for about one pound per ton less than unroasted quartz.
- The origin of this practice in Victoria is not possible to determine because it would have been part of many miner's general knowledge, and could also have been adopted from other similar practices such as calcining of lime. In fact the process was commonly referred to in 1854 as 'calcining' and it is no surprise that the first quartz kilns had the same design as lime kilns. George Ullrich, the Assistant Geologist of the Geological Survey of Victoria, commented in 1857 that the process had more in common with the calcining of lime than true roasting. He recommended that a more perfect roasting system could separate the gold from the quartz. His advice seems to have been heeded because quartz roasting continued to be practised at such places as Maldon until about 1895; the process was believed to assist in treating difficult ores.
- ↑ Davey, Christopher J. "The origins of Victorian mining technology, 1851-1900", The Artefact, 1996, vol. 19, p.52-62
--Neil Huybregts 11:29, 8 May 2015 (AEST)