In South Germany, north of Zweibrucken, are quicksilver deposits that had considerable importance near the end of the thirteenth century, but at the beginning of the World War the mines had been closed for many years. Zinc ores mined near Bensberg, east of Cologne, yield annually about 90 flasks of quicksilver, won as a by-product in zinc smelting. In the former Austrian Empire the principal deposit is at Idria, about 28 miles from Trieste. The ore body occurs chiefly as an impregnation of Triassic dolomite and shale. The output in Austria in 1916, probably all from Idria, is believed to have been about 25,000 flasks. Reserves capable of yielding 20,000 metric tons, or 587,733 flasks, are known. At latest reports these mines were in the possession of Italy. At Zips, in northern Hungary, quicksilver is obtained as a by-product from iron ore (siderite) that carries mercurial tetrahedrite and some cinnabar. The production in 1913 was 2,615 flasks.
To the west of Idria, quicksilver deposits belonging to the same general belt of metallization extend into northern Italy. The principal deposit of this belt in Venetia is the Vallalta. The mine produced 9,550 flasks (325 metric tons) between 1856 and 1870, but has long been idle. The most productive deposits of quicksilver in Italy are those of the Monte Amiata district, in Tuscany, about half way between Rome and Florence. Monte Amiata is apparently a post-Pliocene volcano, and traces of recent volcanic activity survive. The most productive mine is the Abbadia-San Salvatore, which yields about 65 per cent. of the output from the district, which in 1917 amounted to about 29,300 flasks.
At Mount Avala, near Belgrade in Serbia, deposits of quicksilver ore have been known since 1883, which resemble many of those in California. The Avala deposits were worked between 1889 and 1895, but seemingly have not been productive in late years.
The only quicksilver deposits of note in European Russia are those in the Donetz coal basin, southern Russia. The essential mineral is cinnabar, accompanied by stibnite and pyrite. The deposits were discovered in 1879, the maximum output, 18,102 flasks (616 metric tons), was reached in 1897, and work was abandoned in 1911, but has been resumed since in a small way.
Asia.
—The Konia mine, in south-central Asia Minor, is in silicified limestone. The quicksilver occurs as cinnabar and most of the ore carries from 1 to 2.5 per cent. of the metal. The known reserves were estimated in 1908 at 13,000 metric tons of 1 per cent. ore. The production in 1911 was only 90 flasks of 75 pounds. The Kara-Burnu mine, said to be the only important quicksilver mine in Turkey, is situated southeast of Smyrna. In 1906 and 1907 the mine was producing about 3,000 flasks annually, but of late years the output has declined and in 1912 amounted to only 811 flasks (31 metric tons).
The Ildekansk quicksilver mine, in southeastern Siberia, east of Lake Baikal, has gained notoriety from the fact that political exiles were condemned to mine the ore. The deposit appears to be of slight economic importance.
That quicksilver deposits occur in the Province of Kweichow, south-central China, has long been known, but the locality is remote from ordinary routes of travel and comparatively little is on record concerning their character. The ore bodies of the Wan San Chang mines are the most extensively worked. For several years prior to 1905 the output averaged about 4,000 pounds of quicksilver a month. This would be equivalent to about 640 flasks annually. More recent figures of production are not available.
North America.
—The quicksilver deposits of North America are confined to the Cordilleran region from Alaska to Central America. The most productive deposits are in California and western Texas. In Alaska minerals containing quicksilver have been found in a number of the placer-mining districts, but deposits in place have been discovered in the central Kuskokwim region only. The ore occurs as cinnabar accompanied by stibnite, quartz, and a ferruginous dolomite. Development has been hindered by transportation difficulties, and only a few hundred pounds of quicksilver have been produced for local consumption. In Washington quicksilver ores have been prospected in various places, but the production is as yet inconsiderable. In Oregon cinnabar is widely distributed, but only one deposit (at Blackbutte, in Lane County) is at present productive. In the Black Butte mine the ore averages about 0.25 per cent. of quicksilver, and the quantity available above the 500-foot level is estimated by the company at about 150,000 tons. The production of Oregon in 1917 was 388 flasks, all but 3 flasks being from the Black Butte mine.