Los Angeles herald., 1891-10-25
An Interesting Paper by
GerVaise Purcell.
A Number of Novel Statements
About the Useful Metal.
The History of the Mines-Where
Deposits Are Found.
The Southern California Mines-rechni-
cal Features of the Ore
and Milling.

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of the chamber of commerce on the
evening of the 10th inst, from which
the following article is taken:l
Mr.. President and Gentlemen.
lam here this evening in response to
your request to talk about tin. To US of
Southern California this is an inn
pOrtant question and can only wish
felt better able to handle this subject.
| will divide my remarks into three
heads, productive, Commercial" and
political.
Tin is the earliest known metal; his
tory tells Of the trade done in it between
the Phnnicians and the early Britons.
This undoubtedly came from the out
groupings of the Cornish lodes.
Tin is but sparsely distributed over
the globe, being so far only
Bohemia, Hungary, Malacca, Aus
tralia, South Dakota, Southern
California, Chile and Mexico. 1t prin-
cipally occurs as an oxide of tin, COM
posed of: Tin, 1850; oxygen, 21.50;
iron, OBS; silica, 0.75: total, 100. The
other metals occurring with it ale ar
senic, copper and zinc. When worked
from veins it produces block tin, but
when worked from alluvial soil it pro-
duces stream tin, a purer product than
the former.
Cornwall is by far the most important
tin country in the world, both on ac-
count of its quantity and the vast expe-
rience of its people in this industry,
reaching, as it does, back for so many
centuries.
From the ore to its final market tin
passes through FIVE stages. First, the
ore; second, cassiderite or black tin;
third, the white metal or block tin
fourth, tin plate; fifth, terne plate.
The Cornish ore lies in beds running
east and west, and dip all the way from
ten inches to three feet per fathom. The
gangue or matrices of tn g ore are gram
Ite, and while the Cornish mines cover
very large area, and produce great
quantity; still the ore is very low
grade, averaging only 21a per cent. 1t
is also mined at very great depths, va
rying from 100 fathoms to $50 fathoms,
and in the case of the celebrated Dol
coath mines, che depth is 470 fathoms,
over one-half mile. This mine is near
the town OF Camborne, and its opera
tions are a sample of all other mines in
Cornwall. In Cornwall they do not
smelt their tin; this is done in Wales,
where the cassiderite is sent. After the
ore is extracted it is pulverized into
pulp and run over the builders. or as we
say here, tanners. Then the cassiderite
or black tin is ready for smelling. Cas-
siderite contains about 65 per cent. OF
tin. 1t is then sold to about seven To-
cal companies, and leaves Cornwall for
Wales.
The Dolcoath mine employees from 700
to 800 men, and has an output of $50
tons in four weeks. On this output the
company pays every twelve weeks a
dividend Of Ell per share on 5000 0shares.
The mines agent draws 9300 per an
mum, and the men 81 ($5) per week, or
83115 cents per day. The average of the
ore is 215 per cent. will recall these
figures for comparison later on.
The cassiderite, when it arrives at the
furnace, is smelted with coal and run off
into the purifier, and from thence into
the blocks ready for market. The fur
mace charge consists of: Cassiderite
$500, coal 1000, lime 2.00-100.00.
The block tin is ready now for market
and fetches about 99l per ton in Eng
land. 1t is then handed over to the tin
of recent origin in England, having been
introduced in 1920 by Ed. Yarranton,
from Bohemia. The steel plate is coated
with pure tin for tin plate, and with tin
and lead for terne plate.
The next most important deposit of tin
in the world is undoubtedly found in
Malacca. The first discovery was made
in alluvial beds and produced stream
tin. The Cornishmen fondly hoped
that when these alluvial beds were
worked out it would end. But lately
vast lodes of it are said to have been re.
covered and it threatens to become q
great competitor with the English
mines. Now, the Australian mines dc
not present any such danger, being
neither extensive nor of high grade.
In the United States two important
deposits of tin are found, one in South
Dakota and one in Southern California.
OF the former but little is known, ex-
cept that the owners are expending vast
sums in acquiring property, and own
HOO claims of ten acres each, which
they have gradually absorbed, be-
sides owning 1900 acres OF alluvial
beds. The mine is called Harvey
peak and is situated near Rapid City,
s. d. They are said to be milling 200
tons per day, but none of it is yet on
the market. l have seen the Harvey
peak ore and regret / have not speci-
men to show you, as it is very beauti-
full. The gangue is granite and
quartz; great flakes of mica occur
like fish scales. The tin crystals are
said to be the largest in the world and
the metal produced the purest.
| have kept to the last the description
of the Southern California mines as a
fair windup to the subject, being the
most interesting to US here, being, as it
is, right in our midst. The mines
OF the San Jacinto estate are sit
mated in the Temescal mountains lying
easterly from South Riverside. This
range is spur Of the Sierra Nevadas,
which here breaks through the Coast
Range, and presents very much older
formation and one less broken. We
leave behind the broken formation
of the Sierra Nevadas for a
formation more reliable as an ore
bearing stratum. In thu $4,000 acres
comprising this property some. thirty
different lodes have been found extend
ing over four and one-half miles. OF
these lodes only one is worked so far,
the Caialco, but some OF the other lodes,
as prospected, give better promise than
the one already worked. The Caialco
lode yields an ore that gives a percent
age OF from per cent. to 35 per cent. oi
tin. and an average of TX per cent.
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