+-----------+-----------+-----------+-----------+
| Period. | Oz. | Period. | Oz. |
+-----------+-----------+-----------+-----------+
| 1801-1810 | 590,750 | 1856-1860 | 6,350,180 |
| 1811-1820 | 380,300 | 1861-1865 | 5,951,770 |
| 1821-1830 | 472,400 | 1866-1870 | 6,169,660 |
| 1831-1840 | 674,200 | 1871-1875 | 5,487,400 |
| 1841-1850 | 1,819,600 | 1876-1880 | 5,729,300 |
| 1851-1855 | 6,350,180 | -- | -- |
+-----------+-----------+-----------+-----------+
The average annual world's production for certain periods from 1801 to
1880 in ounces is given in Table I. The average production of the five
years 1881-1885 was the smallest since the Australian and Californian
mines began to be worked in 1848-1849; the minimum 4,614,588 oz.,
occurred in 1882. It was not until after 1885 that the annual output of
the world began to expand. Of the total production in 1876, 5,016,488
oz., almost the whole was derived from the United States, Australasia
and Russia. Since then the proportion furnished by these countries has
been greatly lowered by the supplies from South Africa, Canada, India
and China. The increase of production has not been uniform, the greater
part having occurred most notably since 1895. Among the regions not
previously important as gold-producers which now contribute to the
annual output, the most remarkable are the goldfields of South Africa
(Transvaal and Rhodesia, the former of which were discovered in 1885).
India likewise has been added to the list, its active production having
begun at about the same time as that of South Africa. The average annual
product of India for the period 1886 to 1899 inclusive was L698,208, and
its present annual product averages about 550,000 oz., or about
L2,200,000, obtained almost wholly from the free-milling quartz veins of
the Colar goldfields in Mysore, southern India. In 1900 the output was
valued at L1,891,804, in 1905 at L2,450,536, and in 1908 at L2,270,000.
Canada, too, assumed an important rank, having contributed in 1900
L5,583,300; but the output has since steadily declined to L1,973,000 in
1908. The great increase during the few years preceding 1899 was due to
the development of the goldfields of the North-Western Territory,
especially British Columbia. From the district of Yukon (Klondike, &c.)
L2,800,000 was obtained in 1899, wholly from alluvial workings, but the
progress made since has been slower than was expected by sanguine
people. It is, however, probable that the North-Western Territory will
continue to yield gold in important quantities for some time to come.
The output of the United States increased from L7,050,000 in 1881 to
L16,085,567 in 1900, L17,916,000 in 1905, and to L20,065,000 in 1908.
This increase was chiefly due to the exploitation of new goldfields. The
fall in the price of silver stimulated the discovery and development of
gold deposits, and many states formerly regarded as characteristically
silver districts have become important as gold producers. Colorado is a
case in point, its output having increased from about L600,000 in 1880
to L6,065,000 in 1900; it was L5,139,800 in 1905. Somewhat more than
one-half of the Colorado gold is obtained from the Cripple Creek
district. Other states also showed a largely augmented product. On the
other hand, the output of California, which was producing over
L3,000,000 per annum in 1876, has fallen off, the average annual output
from 1876 to 1900 being L2,800,000; in 1905 the yield was L3,839,000.
This decrease was largely caused by the practical suspension for many
years of the hydraulic mining operations, in preparation for which
millions of dollars had been expended in deep tunnels, flumes, &c., and
the active continuance of which might have been expected to yield some
L2,000,000 of gold annually. This interruption, due to the practical
prohibition of the industry by the United States courts, on the ground
that it was injuring, through the deposit of tailings, agricultural
lands and navigable streams, was lessened, though not entirely removed,
by compromises and regulations which permit, under certain restrictions,
the renewed exploitation of the ancient river-beds by the hydraulic
method. On the other hand, the progressive reduction of mining and
metallurgical costs effected by improved transportation and machinery,
and the use of high explosives, compressed air, electric-power
transmission, &c., resulted in California (as elsewhere) in a notable
revival of deep mining. This was especially the case on the "Mother
Lode," where highly promising results were obtained. Not only is
vein-material formerly regarded as unremunerative now extracted at a
profit, but in many instances increased gold-values have been
encountered below zones of relative barrenness, and operators have been
encouraged to make costly preparations for really deep mining--more than
3000 ft. below the surface. The gold product of California, therefore,
may be fairly expected to maintain itself, and, indeed, to show an
advance. Alaska appeared in the list of gold-producing countries in
1886, and gradually increased its annual output until 1897, when the
country attracted much attention with a production valued at over
L500,000; the opening up of new workings has increased this figure
immensely, from about L1,400,000 in 1901 to L3,006,500 in 1905. The
Alaska gold was derived almost wholly from the large low-grade quartz
mines of Douglas Island prior to 1899, but in that year an important
district was discovered at Cape Nome, on the north-western coast. The
result of a few months' working during that year was more than L500,000
of gold, and a very much larger annual output may reasonably be
anticipated in the future; in 1905 it was about L900,000. The gold
occurs in alluvial deposits designated as gulch-, bar-, beach-, tundra-
and bench-placers. The tundra is a coastal plain, swampy and covered
with undergrowth and underlaid by gravel. The most interesting and, thus
far, the most productive are the beach deposits, similar to those on the
coast of Northern California. These occur in a strip of comparatively
fine gravel and sand, 150 yds. wide, extending along the shore. The gold
is found in stratified layers, with "ruby" and black sand. The "ruby"
sand consists chiefly of fine garnets and magnetites, with a few
rose-quartz grains. Further exploration of the interior will probably
result in the discovery of additional gold districts.
Mexico, from a gold production of L200,000 in 1891, advanced to about
L1,881,800 in 1900 and to about L3,221,000 in 1905. Of this increase, a
considerable part was derived from gold-quartz mining, though much was
also obtained as a by-product in the working of the ores of other
metals. The product of Colombia, Venezuela, the Guianas, Brazil,
Uruguay, Argentina, Chile, Bolivia, Peru and Ecuador amounted in 1900 to
L2,481,000 and to L2,046,000 in 1905.
In 1876 Australasia produced L7,364,000, of which Victoria contributed
L3,084,000. The annual output of Victoria declined until the year 1892,
when it began to increase rapidly, but not to its former level, the
values for 1900 and 1905 being L3,142,000 and L3,138,000. There has been
an important increase in Queensland, which advanced from L1,696,000 in
1876 to L2,843,000 in 1900, and subsequently declined to L2,489,000 in
1905. There has been no increase, and, indeed, no large fluctuation
until quite recently in the output of New Zealand, which averaged
L1,054,000 per annum from 1876 to 1898, but the production of the two
years 1900 and 1905 rose to L1,425,459 and L2,070,407 respectively. By
far the most important addition to the Australasian product has come
from West Australia, which began its production in 1887--about the time
of the inception of mining at Witwatersrand ("the Rand") in South
Africa--and by continuous increase, which assumed large proportions
towards the close of the 19th century, was L6,426,000 in 1899,
L6,179,000 in 1900, and L8,212,000 in 1905. The total Australasian
production in 1908 was valued at L14,708,000.
Undoubtedly the greatest of the gold discoveries made in the latter half
of the 19th century was that of the Witwatersrand district in the
Transvaal. By reason of its unusual geological character and great
economic importance this district deserves a more extended description.
The gold occurs in conglomerate beds, locally known as "banket." There
are several series of parallel beds, interstratified with quartzite and
schist, the most important being the "main reef" series. The gold in
this conglomerate reef is partly of detrital origin and partly of the
genetic character of ordinary vein-gold. The formation is noted for its
regularity as regards both the thickness and the gold-tenor of the
ore-bearing reefs, in which respect it is unparalleled in the geology of
the auriferous formations. The gold carries, on an average, L2 per ton,
and is worked by ordinary methods of gold-mining, stamp-milling and
cyaniding. In 1899, 5762 stamps were in operation, crushing 7,331,446
tons of ore, and yielding L15,134,000, equivalent to 25.5% of the
world's production. Of this, 80% came from within 12 m. of Johannesburg.
After September 1899 operations were suspended, almost entirely owing to
the Boer War, but on the 2nd of May 1901 they were started again. In
1905 the yield was valued at L20,802,074, and in 1909 at L30,925,788. So
certain is the ore-bearing formation that engineers in estimating its
auriferous contents feel justified in assuming, as a factor in their
calculations, a vertical extension limited only by the lowest depths at
which mining is feasible. On such a basis they arrived at more than
L600,000,000 as the available gold contained in the Witwatersrand
conglomerates. This was a conservative estimate, and was made before the
full extent of the reefs was known; in 1904 Lionel Phillips stated that
the main reef series had been proved for 61 m., and he estimated the
gold remaining to be mined to be worth L2,500,000,000. Deposits similar
to the Witwatersrand banket occur in Zululand, and also on the Gold
Coast of Africa. In Rhodesia, the country lying north of the Transvaal,
where gold occurs in well-defined quartz-veins, there is unquestionable
evidence of extensive ancient workings. The economic importance of the
region generally has been fully proved. Rhodesia produced L386,148 in
1900 and L722,656 in 1901, in spite of the South African War; the
product for 1905 was valued at L1,480,449, and for 1908 at L2,526,000.
The gold production of Russia has been remarkably constant, averaging
L4,899,262 per annum; the gold is derived chiefly from placer workings
in Siberia.
The gold production of China was estimated for 1899 at L1,328,238 and
for 1900 at L860,000; it increased in 1901 to about L1,700,000, to fall
to L340,000 in 1905; in 1906 and 1907 it recovered to about L1,000,000.