SCIENCE AND INDUSTRY. 
White Earthenware Investigations. 
(From the following Progress Report of the Special Committee, at 
Ballarat, appointed hy the Institute of Science and Industry to investi- 
gate the manufacture of white earthenware in Australia, it will be seen 
that a considerable amount of very useful work has been done, and that 
valuable data have been obtained. Unfortunately there has been delay in 
securing special machinery required for the manufacture of various 
articles, but upon its arrival it is expected that practical demonstration 
of the fact that the Committee has gone a long way towards the solution 
of the problem it is engaged upon will be possible.) 
Kaolins.—As previous work had demonstrated the fact that ample 
_ supplies of high-grade kaolin are to be found in the Ballarat district no 
further samples of this clay were tested. 
Ball Clay.—Although Victoria is well provided with white semi- 
plastic kaolins, yet considerable difficulty has been met with in obtaining 
a good plastic ball clay. Large supplies of sub-basaltic clays occur in 
the neighbourhood of Melbourne, but have first to be tested. One of 
the likeliest areas is the neighbourhood of the great valley of Victoria 
which extends from Dandenong to Bairnsdale. Samples of clay were 
accordingly obtained from Gormandale, Morwell, Longford, Flynn’s. 
Oreek, Moondarra, and Won Wron. Samples of the clay overlying the 
lignite deposit at Lal Lal were obtained from the bores that were 
recently put down by the Victorian Mines Department, and a shaft was 
sunk in order to obtain,a bulk sample. The results of a large number 
of tests carried out on clays from the above localities prove that the 
ball clays investigated up to the present are not as plastic as in England. 
This necessitates a greater proportion of ball clay in the biscuit, and a | 
consequent loss of whiteness in the finished biscuit. 
Cornish Stone—A very important essential in. the manufacture of 
white earthenware is the felspar. As pure felspar is not very plentiful 
in Victoria, it was decided to employ a felspathic material known as 
pegmatite or Cornish stone. It is most important that this material 
should be absolutely free from biotite, as this mineral causes black 
specks in the finished ware. Bulk samples of Cornish stone were 
obtained from selected localities in N.E. Victoria; that from Tallan- 
gatta proved of little use owing to the presence of small quantities of 
iron, but the sample from Barnawartha has been found suitable for 
commercial use. As the tonnage of suitable Cornish stone located up 
to the present is not large, it is intended to make a careful examination 
of the occurrences of pegmatite in this area. 
Constituents of Bodies.—< series of parallel tests were run in order 
to show the comparison between quartz and flint in earthenware bodies. 
Although a great number of cases were tried, it appears that quartz 
serves to supply the free silica quite as effectively as flint. As quartz 
is much more easily obtained in Victoria, it was decided to use it in 
place of the flint. 
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