Sources of Silver.
Strictly speaking, silver mining does not exist as a distinct operation
in Great Britain, for it can hardly be said that this country possesses
any great quantity of silver ore. Yet we must not disguise or leave
unnoticed, in dealing with this subject, the positive fact that silver
is found to some extent in our copper and lead mines, principally
in the latter; but in no case, as far as we know, have mines been
worked for the sake of the silver alone. It is almost always found
in conjunction with lead, and it is from that source that we have a
good supply of British silver. The average annual yield in the British
Isles for some years has been equal to 800,000 ounces--a position in
regard to the quantity produced ranking second only to Spain amongst
the nations of the world, America, of course, being excepted. Silver is
found in a native state, the commonest ore being a sulphuret.
The chief European supplies are derived from Spain, in which country
genuine silver ore exists; from Saxony and Prussia, where the ores are
principally associated with lead, as in England; and from Austria,
where it is for the greater part found mixed with copper. Silver is
nearly always to be found in copper and lead mines, but generally in
such small quantities that it is rarely worth the trouble and expense
of separation.
Considerably more than three-fourths of the whole total supply of
silver comes from America; and in fact nearly the whole territory of
America is said to be more or less argentiferous. Until lately Mexico
carried off the palm, as containing and yielding the largest percentage
of silver; but through the discovery of another mine in the United
States, at Nevada, of considerable richness, which has yielded enormous
supplies, we shall not be far wrong in pronouncing the silver mines in
the State of Nevada to be the richest in the whole world. The extensive
production of these mines, combined with other causes, has led to a
considerable depreciation in the value of silver, and probably this may
yet lead to its more extensive employment in the arts and manufactures;
and, in the midst of the very general depression of the jewellery
trade, any change extending in that direction would be joyfully
accepted by the thousands of workmen in the precious metal trades now
standing idle. We are told that, since the year 1860, the production of
silver has increased from an average yield of eight or nine to fourteen
millions per annum, or about 60 per cent.; while, on the other hand,
the foreign demand for the metal (formerly largely employed for the
currency) has greatly diminished. The rise in cost of silver during the
war years and those immediately following necessitated an Act in Great
Britain "to amend the law in respect of the standard fineness of silver
coins current in the United Kingdom and in other parts of His Majesty's
Dominions."
The chief sources of supply in the British Isles, according to
Professor George Gladstone, are as given below; and as all the silver
found in this country is produced from lead ores, the average yield
here given must be understood to exist in about that proportion to
every ton of lead ore assayed:--Isle of Man, 50 to 60 oz.; Cornwall,
about 30 oz.; Devonshire, about 30 oz.; Cardiganshire, 15 to 20 oz.;
Montgomeryshire, 15 to 20 oz. Thus, it will be seen the lead ores of
the Isle of Man yield the greatest proportion of silver in the British
dominions. Silver is also found in the undermentioned counties, in
all of which it is produced from lead ore:--Cumberland, Durham, and
Northumberland, Denbighshire, Flintshire, and Derbyshire; but the
percentage is much smaller than in the preceding cases. Ireland also
yields a fair percentage of silver.