Hi,
basically "Tozing" (also known as Tossing or Terloobing) is the process
of stirring a slurry of (tin) concentrate in a kiev (large open topped,
round wooden tub) with long handled Cornish shovels. (Usually by two persons
with a shovel each). The object of the process is to get the fine solids
into suspension, then slowly slow down the rate of stirring so that the
heavy high grade concentrate drops to the bottom, followed by progressively
less dense material. When the process is finished, the settled solids (by
assay grade) would resemble a layer cake, with the high grade at the bottom.
The water is then drained off (packing) by hitting the side of the kiev with
a large wooden mallet, thus compacting the void spaces between the grains &
bringing the water to the top. The water being siphoned off. Then the low
grade wood be dug out, followed by mids & high grade...........the values
being checked by the use of a Vanning shovel.
There were mechanically driven Tozing & packing kieves at the tin floors at
Geevor Tin mine in use up until the mid 1960's.
The mechanism for driving the stirring device & raising / lowering the
device was still in place in 1992.
This process was also used at Tolgus tin, but the kievs were made of rolled
steel plate, with a large boss on one side for a mechanically driven striker
to effect the packing operation.
There is also a reference to this I believe in Bryan Earl's book "Cornish
Mining" to Tozing .
Hope this is of help.
Regards, bob Orchard.
----- Original Message -----
From: "Jim Besleme" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, February 24, 2005 12:40 PM
Subject: Re: Tozing
> In a message dated 2/23/2005 5:37:04 P.M. Central Standard Time,
> [log in to unmask] writes:
>
> I am currently compiling a glossary for a forthcoming Tamar Mining Press
> publication on ore dressing at Devon Great Consols (watch this space)and
I
> am having problems defining tozing - can anybody help?
>
> Rick Stewart
>
>
>
> Rick,
>
> I Googled it and got..................or tossing .An ore processing term.
> Tozing is a means of separation of ore by violently agitating the slimes
in
> water. The ore settles first leaving the waste on top.
>
> Jim Besleme
>
>
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