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76 and at once began prospecting near Bathurst on the Macquarie river, New South Wales, where gold was found in considerable quantities. The announcement of this fact caused much excitement and a sudden immigration of great magnitude to this region. (See ). The government at once laid claim to the land and began to grant licenses to dig for gold. The gold region was soon traced along the range of hills N. and S., and new discoveries were made of deposits surpassing all the rest in richness in the colony of Victoria, near the southern coast, 70 m. N. W. of Melbourne. In October there were 7,000 persons engaged in the new diggings at Ballarat near Mt. Buninyong, occupying less than a square mile in extent. The next month many of these were drawn off to the still richer deposits about Mt. Alexander in the same region, where it was estimated that 10,000 persons were then employed. In December 63,300 oz. were transported to Melbourne from this locality, which was then valued at £3 19s. 6d. per oz. The whole amount conveyed from the two localities from Sept. 30 to Dec. 31 was 124,835 oz.; the whole product of the colony was 345,146 oz. The immigration the next year of 104,000 more than doubled the population of Victoria; still richer diggings were discovered at Bendigo, and the total product of the colony for the year 1852 was estimated at 4,263,042 oz. The estimates made in London of the whole amount of gold exported from Victoria and New South Wales up to the close of 1852 gave for the former a total value of £16,000,000, and for the latter £3,500,000; or for 15 months nearly four times what the annual production of the world was supposed to be five years previously. The richest and most extensive gold fields of Australia are in the colony of Victoria, where the area of the mining region is about 725 sq. m. This is divided into the mining districts of Ballarat, Beechworth, Sandhurst, Maryborough, Castlemaine, and Ararat. In Australia, as in California, gold is directly obtained from three distinct sources, viz.: shallow placers, deep diggings, and quartz veins. The estimated number of quartz veins in Victoria is about 2,000. According to Selwyn, “these veins, traversing lower palæozoic strata and associated with granitic and igneous rocks, are, so far as at present known, the primary source of the whole of the gold raised in Victoria. The thickest and most persistent veins, or lines of reef, are found on the lower or older portions of the series; but the average yield of gold per ton of stone has, I believe, been greater from the thinner veins of the upper beds.” The thickness of these veins, which are described as “dikes or reefs,” varies from that of a thread to 130 ft. They have a general meridional direction, and are inclined either east or west at angles varying from horizontal to vertical. Frequently they occur in the planes of cleavage, occasionally between those of the strata, and they often

intersect both. These veins have been worked to a depth exceeding 600 ft., and it has been found that the yield does not decrease with increase of depth. Mr. Selwyn has reached the conclusion that at least two distinct sets of quartz veins exist in Australia, one of which is entirely barren, and that they have been formed at two different and remote periods, the barren being the older one. This view is corroborated by the fact, well known to experienced quartz miners in Australia, that in many districts barren and rich quartz ledges are found in close proximity. As this same phenomenon has been noticed in California and the Appalachian gold field, it suggests, according to Blake, the probable existence of quartz lodes of two or more distinct periods in America as in Australia. The greater portion of the gold obtained in Australia is from gravel deposits or placers similar to those in California. They occur in beds of streams, along the banks, and in ancient channels running transversely to the existing drainage of the country. Rich deposits are found under heavy accumulations of stratified tuffs and lavas overlaid with table mountains of basalt. The thickness of the placer deposits varies greatly in different places, ranging from 100 to 400 ft. The ratio of gold obtained from quartz mines to that of placers is indicated by the production of the two kinds in Victoria in 1866, viz., 521,017 oz. of quartz and 958,177 oz. of placer gold. The most productive gold fields of Victoria have been those of Ballarat and Bendigo. The general description of the gold fields of Victoria will apply to those of New South Wales. The alluvial deposits, however, are not so extensive as in Victoria, and the production of the colony has been less. South Australia and Queensland are also gold-producing, but the amount obtained is small. The Australian gold has a higher color and is finer than that from California. Its fineness ranges from 20 to 23.5 carats, the Ballarat gold being of the highest standard. The Ballarat nugget mentioned above, found in 1858, and weighing 2,217 oz. 16 dwts., was exhibited at the Paris exposition of 1867, and valued at nearly £10,000. Gold was first discovered in New Zealand in 1842; further discoveries were made there in 1851, and in 1856 mining operations on an extensive scale were begun. The rock formations and alluvial deposits, which are deep and extensive, are similar to those in Australia.—In the United States there are two extensive auriferous regions or gold belts, one on the Atlantic slope, known as the Appalachian gold field, and the other on the Pacific coast, embracing California and the neighboring states and territories. The Appalachian gold field extends southwesterly from Virginia through North Carolina, South Carolina, and Georgia, and also includes portions of Alabama and Tennessee. The width of the gold range varies greatly; in some places it exceeds 75 m. The metal does not exist in a continuous belt