Peter,
Apologies for tardy response, but, not being online at home, I access my emails at intervals.
I
have quite an amount of data on the history and practice of flotation in
Cornwall, which I could send you as a ‘Word’ doc. attachment - there being far
too much to put in an email - including references, some Elmore history, and
operating results and recoveries for both the early ‘Bulk Oil’ and the later
‘Vacuum’ copper recovery plants put in at Tywarnhayle. The remains visible on
the mine site today relate to the latter, on a steep hillside, and consist of
an array of concrete loadings that are not easy to interpret fully. I have
pictures, illustrations and diagrams of both types of Elmore process. It is interesting
to speculate on what the result of the famous lawsuit would have been had it
been heard in England
instead of the U.S.A?
Aside
from this mine, there were three other Elmore vacuum flotation plants installed
in Cornwall
prior to 1910 specifically for copper - at Dolcoath (unit diagram and some
operating results), Falmouth Consolidated and Gunnislake Clitters.
(Other
Cornish mines (10 of them) later put in more conventional cell-flotation plants
at one time or another to remove bulk sulphide minerals during processing of
tin ore, but, of course, these were not specifically for copper, though a few
small parcels were probably sold by some from time to time. There was also the
invention of the Holman-Michell table flotation process (or ‘skin’ flotation)
for coarse sulphide particles.
Early
experiments in tin flotation went on at six Cornish mines during the 1920s, and
at least one trial on silver-bearing lead ore at a small mine in mid-Cornwall
in 1920. This project was not continued, probably for lack of sufficient
payable ore.)
Don’t
forget the plants at both the ‘New’ Wheal Jane, and Mount Wellington,
which, in their first incarnations in the 1970s, made separate copper and zinc concentrates by flotation (mill flowsheets
available).
Regards,
Tony
Clarke
> Date: Tue, 1 Nov 2011 20:14:37 +0000
> From: [log in to unmask]
> Subject: Copper Concentration in England
> To: [log in to unmask]
>
> I am working on the first draft of the Copper section of the NAMHO Research framework for the Archaeology of Extractive Industries in England, for English Heritage. Thinking specifically about copper concentration, I would like to know whether there were any flotation plants built primarily for copper ores in England?
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