Page 20 - Bulletin 14 2010

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order to release the fine particles of the tin-bearing cassiterite from the surrounding matrix of
silica, the crushed material was fed into a long series of concrete troughs or flumes. (Fig.

1.10.) Arranged so that they touched end-to-end, but with each trough slightly lower than the
preceding one, a stream of water, pumped from the adjoining stream, flowed along the line of

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troughs. The particles of cassiterite, with a density of c. 7 g/cm , would sink through the
flowing water to the bottom of the trough while the particles of silica, with a density of only
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2.2 g/cm , would be carried further by the stream of water, thereby effecting a separation.
From time to time the cassiterite – known as ‘concentrate’ – was removed from the troughs,
bagged and sent to Cornwall for conversion into metallic tin.

Inside the mine itself a second vertical shaft, now completely flooded, was sunk from near the

base of the main vertical shaft. This was presumably done in an attempt to intersect further

tin-bearing ore lying further below ground level, and its existence is strong evidence that the
veins which had previously been worked had now petered out – as is clearly evident from an

inspection of the mine today. Various other exploratory drives (i.e. horizontal passages) were

also driven from near the base of the main vertical shaft but clearly none succeeded in
intersecting further payable ore.

The labour force on the mine had meanwhile grown steadily and the Government Gazette for

January 1912 not only mentions the five-stamp battery but also reports that there were eleven
‘Europeans’ employed on the site, as well as forty-three ‘Coloured’ labourers underground

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and forty-two on the surface, giving the remarkable total of almost a hundred men. (Fig.
1.11.) It is also mentioned that the manager of the mine was the brother of A. C. Ross, the
original prospector.

This period represents the high-water mark of the mine for soon afterwards the number of

men employed began to drop sharply. The official records show that by march 1912 only
eleven ‘Whites’ and thirty ‘Coloureds’ were employed on the mine, while by May these

figures had dropped to two and seven respectively. A report prepared by the Office of the

Government Mining engineer shows all too clearly that by now the mine was in serious
trouble, for while in November 1911 it had produced 430 tons of ore, by March 1912 this had

fallen to 107 tons. Thereafter nothing further was produced and, as the report sadly states,