GOLD MINES AND MINING OPERATIONS.

Otago Daily Times, Issue 805, 12 September 1864, Page 6

GOLD MINES AND MINING OPERATIONS.

No. 11,

DISTRIBUTION OP GOLT>. — ETTROPB :—RUSSIA, HOKGAKT AND TRAHSYLTANIA, SAXONY, PRASC3, 6PAIH, PORTUGAL, SWEDEN, SARDINIA, WALES, HSGLASB, SOOTIAND, IRELAND.—-ASIA :—SIBERIA, OfllNA, HINDOSTAN, TONQUIN, JAPAN, BORNEO, ISDIAN AROHIPEI.AGO-—AFRICA:-THE GOLD OOA&T, ABHANTEB, BAHBOUK, BOFAL4. ~ SOUTH AMERICA:-CHILI, PERU, BOLIVIA, ECUADOR, NEW GRANADA, BRAZIL, CENTRAL AMERICA.—NORTH AMERICA :-CALIFORNIA. —-REMARKABLE GEOGRAPHICAL FEATURE : BRITISH COLUMBIA. — MEXICO. — THE UNITED STATES.—CANADA.— AITS RLAIA. — J HEW ZEALAND —OTAGO. — MINING 111- j PLEMENTS. Gold is far more widely distributed throughout the world than is generallysupposed. Adolph Erman has appended a map to his Geoqraphische Verbreiiuns? des Goldes, (Berlin, 1848), in which he j indicates seventy-seven tracts in which gold has been worked, or is still known to exist; and shows, in contradiction to the commonly-received opi -ion, how greatly it predominates in the Northern Hemisphere. Of the five great divisions of the earth, Europe is at present one of the smallest contributors; producing in fact but a comparatively insignificant quantity. The Ural, or Oural Mountains, which constitute the north-eastern boundary of European j Russia, are indeed rich in the precious ! metal. By far the largest proportion, however, is there obtained on the eastern slopes of that great chain, and in the streams which descend from them, and is therefore more properly derived from Asiatic Russia. The most important gold mines in Kussia Proper are those of Zlatoustvosk, on the Ai Kiver, the yield of which is stated by the latest available returns to be about 25,000 ounces per annntn.

According to the most recent authorities, Hungary with Transylvania, yields half of all the gold now produced in Europe. Mr Paget estimates the quantity annually obtained in Hungary Proper at 1,950 marks, of about the value of i 71,400. It is found at Kremnitz, Schenmitz, and other places in the north, and at Nagy-Banya on the Transylvanian Borders, where it occurs in veins lying on, and in trachyte and porphyry. Transylvania is still richer. Almost all the streams' contain gold, and upwards of twenty mines are in active operation. Small quantities are also obtained in the Tyrol, from auriferous iron pyrites. The total produce of Austria in 1854, is stated by Mr Whitney, at 68,400 ounces; but it is Eaid, that for state reasons, the whole

quantity which reaches the Imperial treasury is not made known. Gold is known to exist in the mountains of Saxony; in the sands of the Moldau and other Bohemian rivers; in those of the Rhone and the Danube; and in the valley of the Rhine, between Bale and Mannheim. In France, also, gold is found in the rivers, and in situ, in thin seams of quartz. None of these, however, are sufficiently rich to pay for working. The go\l mines of Spain, in Galicia, Lusitania, and ths Asturias, whence the emperor Vespasian obtained annually £60,000, are now entirely neglected, although it is certain that they are by no means exhausted. In Portugal small quantities of gold are stil! washed from the sands of the Tagus, the Douro, the Mondego, and other streams, and from several sierras, particularly those of Estrella and Gerez. The workings on the table land of Smaland, in Sweden, are now abandoned, having ceased to be profitable ; as also are those 'of Sardinia and Corsica, in South Europe. Yet we are informed by Pliny, that in the days of the Roman Republic 25,000 men were constantly employed in the rich gold mines of Yercelli, now a Sardinian Province. Auriferous rocks occur in various parts of the British Islands, but they are seldom rich enough to render the working of them remunerative. The Vigra and Clogau mines in North Wales would seem however to be exceptions to the general rule, if a paragraph which has recently gone the round of the English press may be relied upon as correct. According to this authority, " within a fortnight, 3320zs of gold were extracted from 15^-cwt of quartz; and nearly 10,000ozs have been obtained from 1,600 tons of mineral, which gives at the rate of more than six ounces to the ton." _ In 1843 gold was discovered at Cwn-Eisen, in Merionethshire, in a branching lode of hard quartz, running in a north-easterly direction, and containing lead-ore. At Dol-y-frwynog, near Dolgelly, in the same county, a lode of white saccharoid quartz, opened for copper-ore, was found to te richly impregnated with gold. The results of the crushing are thus given in the Encyclopedia Britannica, (Ed. 1858.) "On the 16th August, 1854, they crushed 39 tons of quartz, which yielded at the rateofsozs 9dwts per ton. Afterwards they crushed 100 tons, and found gold at the rate of sozs per ton ; then successively gold at the rates of Bozs 9dwts per ton, and 4ozs 15dwts per ton." Nevertheless, the works were abandoned as unprofitable. Ancient Roman gold-workings have recently been discovered near Pamsant,in Casrmarthenshire. Specimens of native gold are sometimes found in the streamworkkigs of Cornwall, and various parts of Devonshire; and a few years since operatious were undertaken for its extraction from the ferrunginous quartz, known in ' those counties as " gossan." Gold like- ' wise occurs in Cumberland. In Scotland, it has been found -in the Grampian Hills, \ at Glen Turret in Perthshire, Glengaber, in Peebleshire, and near Dunoou, in Argyleshire. Extensive workings were ] formerly carried on in the Lead-hills of Dumfriesshire, where, in the reign of | James V., 300 miners were very pro- ! fitably employed ; and in 1803, Professor j Traill found specimens of gold in a vein of quartz near Wanlockhead, in the same county. In Ireland, gold was accidentally discovered towards the close of the last century, in the streams which descend from the northern flank of Croghan Kinshela — one of the Wicklow mountains—and flow over beds of slate, veined with quartz. Something like a " rush " took place, and considerable quantities of gold were ob- i tamed, principally in nuggets, one of which weighed 22 ounces. The Government took possession of the mines, and wrought them for two years, during which period only 945 ounces were extracted; but the works being destroyed by insurrectionists in 1798, the mines were abandoned, and.have not since been worked. _ j The auriferous regions of Asia are very extensive and productive. The gold-mines of Siberia have already been referred to and described.. It is generally believed that they are mainly wrought under the supervision of the Government; but this is by no means the case, for the private mines contribute nine-tenths of the entire produce. In China gold is procured from several rivers, particularly from the upper branches of the Yang-tse-Kiang; and it 18 also found in the mountainous and almost inaccessible regions of Yunnan. It occurs' in Hindostan, In the streams of the Indian Caucasus, and in some parts of the Tmlo-Chinese Peninsula. The Province of Touquin, in the Empire of Anam, produces large quantities of gold; thousands of people being employed in collecting it from the river beaches The auriferous wealth of Japan is said to be very great, and the island of Sado is particularly mentioned as being rich in gold. In Borneo both gold and diamonds are found in abundance, in a diluvial formation of quartzose gravel, reddened with oxide of iron. The annual produce of the former has been estimated at a quarter of a million sterling; but it is impossible to ascertain the yield with accuracy, as mining operations are carried on exclusively by the Chinese, who crowd to Borneo in great, numbers for that purpose. Gold is also known to exist in Sumatra, and other islands of the Indian Archipelago. Although the total known produce"of Africa is inconsiderable, gold is widely disseminated through a large tract of country in the north-west part of that continent. j The sands of the Niger, the Gambia, the Senegal, and other rivers, yield a certain proportion of gold, and large quantities were formerly exported from the Gold Coast. Ashantee abounds in the precious i metal. The principal mines are in Ganam, ■, where gold occurs in large pieces, or nuggets, some of about four pounds weight. Gold is also found in great quantities on the banks of the Bara, 10,000 slaves being employed in its collection durinir two months in the year. But probably the richest mines in Africa are those of Bambouk, a rugged and mountainous country in Senegambia, possessing an auriferqus area of more than 1200 square miles in extent. The most noted is that of Natakoo, where the gold is found in a small round isolated hill, about 300 feet high and 3000 paces in circumference. Every cubic foot of this hill, which is composed I of an unctuous argillaceous earth (the j " pipeclay" of our miners) is said to be loaded with the precious metal. Isolated mounds of a similar description occur at Nambia, on the east flanks of the Taboura Mountains, and at Kombadyria, in a valley

to the cant of the Rio d'Oro. Forty miles south of Natakoo are the mines of Semay]a, where gold is found principally in the matrix. Gold is also bi'ought from the districts between Darfur and Abyssinia, and a trifling quantity is exported from Sofala, on the Mozambique coast, which is regarded by some authorities as the Ophir of the ancients. The west coast of South America Js traversed by a vast chain of metalliferous mountains, extending continuously through Chili, Peru, Bolivia, Ecuador, and New Grenada, in all which countries silver is obtained in large quantities, and gold in a lesser degree- In Chili the gold is principally procured from sands, detritus, conglomerates, _ and loose debris. la Peru and Bolivia the ancient drift, or diluvium, has afforded the most gold. In the latter country the washing of the sands at the sources of the Rio Grande, as well as at Tipuani, is also carried on with profit. The quantity obtained from these three countries is not very great at present. Mr. Whitney estimates the gross yield of 1854 at about 24,000 ounces. According to the same writer, Ecuador and New Granada produced about 60,000 ounces in that, year ; but more recent authorities estimate the annual yield of New Granada alone at nearly half-a-mil-lion sterling. The chief mines are in Antioquia and the valley of the Cauca. The gold mines of Brazil are for the most part situated at the foot of the great mountain chain, which runs parallel with the coast, from the fifth to the thirtieth degree of south latitude. Gold also occurs in greater or less quantities in the beds of the streams forming the upper branches ot the Francisco, Tocantins, Araguay, and Gaupore rivers, but more particularly in the first. The rock in these localities consists of primitive granite, inclining to g»eiss, and the soil, which from being highly ferruginous, is of a bright red color, often extends to a considerable depth. The gold is chiefly found in a bed of gravel and rounded pebbles called cascaho, immediately in contact with the surface of the solid rock.— (Phillips.) Gold is also procured in the province of Minas Geraes, (where the most valuable mines are worked by an English company, organised in 1852,) and in the vicinity of Villa Rica, where it is found both in alluvial deposits between elevated hills, and mingled with the sands of the rivers. The mines of Venezuela once yielded a large amount of treasure, but were abandoned, in consequence of their supposed exhaustion, early in the seventeenth century. Panama and Nicaragua formerly were, and are still believed to be, rich in gbid. Costa Rica contains some of the most productive gold mines in Central America, which are, however, but little wrought; and only a small quantity is now extracted from the mines of Salvador. The gold-producing districts of California extend northwards from the mouth of the Sacramento River. Sir Roderick Murchison notices a remarkable geographical feature connected with the mineral phenomena of California. The greatest quantity of gold has been derived from localities in that portion of the western flank of the Sierra Nevada, which assumes a northwesterly direction from that parallel to the meridian it had before followed, between 37deg. 30min. and 30deg. North Latitude. This westward deflection is directly opposite to where the extremity of an east and west ridge impinges on the Sierra Nevada, and is associated with the protuberance which alone has proved to be eminently auriferous in the long chain of mountains, ranging from the eternal snows of Russian America, to Mexico, Peru, and Chili. _ It is possible that the intersection of ridges may account for a great local developement of metal, just.as in mining practice it is found that the richest branches are often detected where lodes traverse each other—a fact well known to the quartz miners of Victoria. The principal gold workings of British Columbia are on the Frazer River, but gold has also been found in Vancouver's Island. In Mexico, the only auriferous veins now worked are in Oaxaco, where they traverse formations of gneiss and mica slate. The gold region of the United States is a metalliferous belt extending through Virginia, North and South Carolina, and Georgia. Its length is about 600 miles, and it has a mean breadth of about 80 miles. In every part of this line native gold is met with in alluvial deposits, and in various streams, where the continuous rocky strata abound in auriferous quartzose veins. Parallel belts are also found near Augusta. A moderate amount of gold has been derived from the metamorphic rocks of the Lower Silurian range in Lower Canada; and within the last" tew years larger auriferous deposits have been discovered in that country.— (Ency. Brit) The gold mines of Australia are perhaps the most extensive in the world. The source of the gold appears to be an indefinite succession of clay slate and micaschists, interstratified with quartz-veins; and it is found both in alluvial deposits and in the matrix. The richest mines are those of Victoria—New South Wales producing but little. Isolated patches have been met with in Queensland, but no discovery of value has yet been made. In New Zealand, the principal gold fields are confined to Otago, but other provinces contain gold, either in the alluvia, or in the matrix, as at Cpromandel. The conditions under which it has been found in Otago, and the various processes employed for its extraction, as compared with those of other countries (more especially California, with which New. Zealand presents many features in common), will form the subject of future articles. The ens raving which accompanies this article represents miners engaged working with a "long-torn." A description of this and other machines and implements ordinarily used in gold-mining operations will be given in No. 3, together with an illustration of the more advanced mode of mining, technically known as "groundsluicing." "