The vein-filling is friable, white, crystalline quartz containing stephanite, pyrargyrite, argentite and some native silver. From onethird to one-half the total value is gold. The ore-streak occupies a space of from one to ten feet in the vein. The Buffalo and Monarch mines are probably situated on the same lode.1 At Gibbonsville gold-bearing ores are found in veins cutting siliceous schists, with widths of 18 inches to 3 feet. The value of the ore lies in the sulphides, although fully one-third is recovered by amalgamation. The pyrite contains gold in values from $30 to $130 per ton. The gangue is chiefly quartz and schist. Silver is only occasionally found and where it occurs with the gold the value of the gold is low, ranging from $14 to $18 per ounce. Palladium is said to be present." Isthmus of Panama. - There are numerous gold mines, both grayel and vein workings, in this territory, but comparatively little work has been done by way of development. The gold mines near Emperador may be chosen as a type. The country-rock is porphyry considerably decomposed and traversed by innumerable veins of ferruginous quartz, the gold occurring in the thin seams and crevices. The so-called "red ores" are usually very rich and owe their color to large quantities of peroxide of iron. The veins of the Pacific coast are generally characterized by containing a smaller percentage of sulphides. The bulk of the ores of the Emperador mine range from $5 to $10 per ton, while those on the Pacific side usually run higher, as from $30 to $60 in gold per ton. The gangue is chiefly porphyry and quartz.3 Kansas. Aside from the finding of gold in glacial drift and wash from the mountains on the west, but one authentic occurrence of gold and silver in situ has been reported. Both gold and silver have been found in small quantities in the shales of the Benton group of the Cretaceous in the western central portion of the state, especially in Gove, Trego and Ellis counties." Kentucky. - Silver ore has at various times been claimed to have been found in the shale underlying a conglomerate below the falls of the Cumberland in Whitley County. However, chemical analysis does not corroborate such claims.5 Eng. and Min. Jour., Vol. 59, p. 128. ' Eng. and Min. Jour., Vol. 34, p. 173, 1882, and Ibid., Vol. 6, p. 377. ♦ Eng. and Min. Jour., Vol. 74, p. 111. 5 Report of the Kentucky Geol. Survey, 1856, p. 235. Maine. Gold is found in quartz-veins in mica-schists at Baileyville. It is claimed that there are other similar occurrences in the state, but little attention is paid to such rumors owing to the small amount of values in the deposits. Pyrites occur with the gold especially in depth.1 In 1880 there were fully fifty incorporated mining companies in the state. The chief centers of silver mining were Hancock, York and Knox counties. The leading camps were the Sullivan, Gouldsboro, Cherryfield, Hampden, Franklin, Rockland, Dexter, Blue Hill, Acton, Sedgwick and Carmel.2 To illustrate the extent of the operations the following data of the Sullivan district is given:3 THE SILVER MINES OF THE SULLIVAN DISTRICT. We give below a list of the prominent mines of the Sullivan district, Hancock County, upon which active developments are now going forward: (a) Ore brittle silver in quartz. (b) This company will put in steampower immediately; vein well defined and promising. (c) Shaft 104 feet down; 130 tons of ore on the dump; steam-machinery and pump. (d) This company has a 5-stamp mill and steam hoisting machinery. (e) The vein is well defined, and carries gold. (f) This company has 100 tons of smelting ore out, one-half of which is high-grade; preparing for steam power. (g) This company has 100 tons of ore out, ready for concentration. (h) This ore shows silver. 2 U. S. G. S., 16 Ann. Rept., Pt. 3, p. 328. Special Correspondence to the Eng. and Min. Jour., 1880. The Mount Glines mine, Oxford County, gave, as reported by assay, $7.50 to $49.68 gold. However, the officials of the United States. Geological Survey were not able to obtain any trace of gold (see Bull. 225, 1904). (For analysis see Recent History, Maine.) The country-rock is largely granite, the gangue mineral is quartz while the metalliferous minerals constituting the ore are sulphides of iron and lead. In 1879 the Canna silver mine is said to have yielded ore worth $9 in gold; 37 ounces in silver, with varying amounts of copper and lead. The Home mine on an 18-inch vein yielded, as reported, $22 silver and 20 per cent lead. It was further claimed that there were 1000 tons of $50 ore on the dump. Other more or less important mines considered from the standpoint of the district were: the Golden Circle, the Fort Knox, Gouldsboro, etc. The minerals usually found are galena, gray copper, antimonial silver, pyrite, chalcopyrite, stephanite and arsenical pyrite, which are found in quartz-veins, also veins of pegmatyte, and in contact deposits between limestone and trap dikes.1 Maryland. Gold occurs in veins of quartz on the north side of the Potomac River in Montgomery County. Assays of specimens from this locality are said to have shown values ranging from $168 to $787 per ton. The country-rock is fine-grained micaceous schists, probably more massive than schistose in structure. Some of the quartz-filling of the veins shows free-gold, but the greater part does not. Epidote and chlorite are found associated with the schists as basic silicates. Some pyrite is found in the oxidized zone, below which the sulphides occur as in the mines of the Southern states. It is evident from the work done that the quartz-veins are very irregular in both vertical and horizontal directions.2 ores. Massachusetts. - The mines at Newburyport are spoken of as silver mines, although considerable quantities of gold are found in the The ore-bodies are found in veins which vary in width from three to six feet, although the mineral does not occupy more than 15 inches in width across the vein. The minerals are galena, gray copper, siderite and quartz. An assay made on a sample taken from borings across the vein showed a gross value of $154.14 per ton, of which $69.84 was lead, $72.87 silver and $11.43 gold.3 Besides the Newburyport mines the following were among the 1 Special Correspondence to the Eng. and Min. Jour. during the Eighties. T. A. I. M. E., Vol. 18, p. 391, etc. 3 T. A. I. M. E., Vol. 3, p. 442. more important: the Northampton, Merrimac, Four Rock, Cedar, Bartlett, Gorges and Davis, most of which yielded ore, largely argentiferous galena. Probably the most important of these mines was the Merrimac, which in a report by F. L. Vinton was accredited with 40,000 tons of ore of a value of $94 per ton. The Davis mine at Charlemont produced ore which sold at the mine for $4 and at tide water for $5 per ton.1 At the Merrimac mine the following conditions obtain: The country-rock is granite grading into gneiss and quartzite. The width of the lode is approximately 200 feet, consisting of trap, with masses of quartz and stringers of calcareous clay. The minerals are argentiferous galena and tetrahedrite; the gangue is quartz, fluor-spar, pyrite, blende and chalcopyrite. The ore occurs in a more or less vertical position resembling a chimney of ore.2 Michigan. The presence of native silver associated with the copper of the Lake Superior Copper region has been known from the earliest times. Only a comparatively few of the copper mines of this region show no silver, while the majority yield varying amounts, some in quantities to warrant its separation from the copper, which is seldom or never attempted at the present time. The belt of trap of the extreme northern portion of Keweenaw Point is composed of a variety of igneous rocks known as amygdaloid and granular trap. The amygdaloid is full of vasicles which in turn are filled with carbonate of lime, chlorite, agates, carnelians and amethysts, also minerals of the zeolite family. With depth the vesicular structure disappears and the rock becomes a dark brown granular trap. The belt is traversed by veins containing native copper and silver. Mining has not, however, proven very successful, the more important attempts having been made at Eagle Harbor and Hawe's Island. At the Cliff mine the gangue at the outcrop was prehnite with copper and silver associated, all incrusted with beautiful crystals of red oxide. Above, the width of vein was scarcely over two inches, but with depth a width of several feet is attained, the veinstone consisting of reticulations of laumonite. The silver and copper are not alloyed as would be the case had they been in a state of fusion. Silver and copper often occur intermixed but in such a manner as to be entirely free from alloy 1 Special Correspondence to the Eng. and Min. Jour. and Geol. of New Hampshire, Hitchcock, Vol. 3, Pt. 5, p. 35. 2 Report on the Merrimac mine by F. L. Vinton. |