Chalcocite (copper glance). Deer Lodge County, in small quantities at Cable Clay (fire). Cascade County, dug near Armington and at Fields. Deer Lodge County, Anaconda and Lost Creek. Jefferson County, Whitehall. Lewis and Clark County, Helena. Clay (plastic). See Bentonite. Coal (bituminous and subbituminous). Areas of workable coal are known to exist in the following counties: Blaine, Carbon, Cascade, Chouteau, Fergus, Flathead, Gallatin, Hill, Madison, Missoula, Musselshell, Park, Rosebud, Teton, and Yellowstone. Coal is mined in the following places: Blaine County, Chinook and Harlem. Carbon County, Bear Creek, Bridger, Burgin, Carbon, Fromberg, Joliet, Red Lodge, and Washoe. Cascade County, Armington, Belt, Eden, Geyser, Sand Coulee, and Stockett. Chouteau County, Big Sandy and Mackton. Fergus County, Buffalo Creek, Giltedge, Lewistown, Stanford, Smith, Utica, and Windham. Gallatin County, Chestnut. Hill County, Havre. Missoula County, Missoula. Musselshell County, Roundup. Park County, Cinnabar and Cokedale. Yellowstone County, Bull Mountains. Coal (lignite). Areas of workable lignite are known to exist in Custer. Dawson, Rosebud, Sheridan, and Wibaux counties. Custer County, mined at Miles City and Stacey. Dawson County, Cohagen, Jordan, and Glendive. Sheridan County, Brockton and Culbertson. Wibaux County, Wibaux. Chiefly for local use. Copper ores. Copper is the predominant metal produced in the following districts: Beaverhead County, Beaverhead, Elkhorn, Utopia. Broadwater County, Hellgate. Meagher County, Copperopolis. Missoula County, Denemora, Wallace. Ravalli County, Mineral Point. Silver Bow County, Butte. See also Azurite, Bornite, Chalcanthite, Chalcocite, Chalcopyrite, Chrysocolla, Covellite, Cuprite, Enargite, Malachite, Tennantite, and Tetrahedrite. Copper (native). Deer Lodge County, small quantities in upper level of Cable mine at Cable. Silver Bow County, in oxidized zone of Butte. Corundum. Gallatin County, was formerly mined at Bozeman, Salesville, and headwaters of Elk Creek for abrasive. No abrasive corundum is now mined in Montana. Corundum (sapphire). See Sapphire. Covellite (indigo copper). Jefferson County, Boulder (rare). Silver Bow County, ore of minor importance in Butte mines. Cuprite (red copper oxide). Silver Bow County, minor mineral in ore of Butte district. Enargite. Silver Bow County, next to chalcocite the most abundant copper mineral at Butte. Galena (argentiferous). Beaverhead County, mined in Hecla and Trapper districts. Blaine County, Bearpaw Mountains. Broadwater County, Argenta, Beaver Creek, Crow Creek, Indian Creek, Park, and Winston districts. Cascade County, Barker and Neihart districts. Deer Lodge County, Cable district (rare). Granite County, Philipsburg. Jefferson County, Amazon, Basin, Clancey, Elkhorn, Gregory, Lump Gulch, and Wickes districts. Lewis and Clark County, Bald Butte, Helena, Ottawa, Rimini, and Tenmile districts. Lincoln County, Troy and Snowshoe. Meagher County, Castle Mountain. Mineral County, Iron Mountain. Park County, New World. Powell County, Elliston. Ravalli County, Hamilton (Curlew mine). Silver Bow County, sparingly in silver veins and in some of the later fault veins of the copper area, Butte. Garnet. Madison County, small quantity recovered from gold dredges at Alder Gulch and at Ruby; cut for jewelry. Gold (lode). Widely distributed in southwestern quarter of the State. Principal districts that have produced are: Beaverhead County, Bald Mountain and Bannack. Blaine County, Bearpaw. Broadwater Couty, Lone Mountain, Park, and Radersburg. Deer Lodge County, Cable and Heber. Granite County, Philipsburg and Red Lion. Jefferson County, Cataract, Colorado, and Lump Gulch. Lewis and Clark County, Bald Butte, Helena, Marysville, and Rimini. Lincoln County, Cabinet, Fisher Creek, and Sylvanite. Madison County, Pony, Norris, and Whitehall. Mineral County, St. Regis. Missoula County, Clinton and Ninemile. Phillips County, Landusky. Silver Bow County, Fleecer Mountain, German Gulch, and Highland. Gold tellurides were formerly mined in Fergus County, in Judith Mountains, Spotted Horse mine. Gold (placer). Placer mining, formerly very important, is still carried on to some extent in Broadwater, Chouteau, Granite, Jefferson, Lewis and Clark, Lincoln, Madison, Mineral, Missoula, Park, Powell, Ravalli, and Silver Bow counties. Hydraulic and dredge mining, in the following counties: Beaverhead County, hydraulic near Bannack. Granite County, hydraulic at Bear Gulch and Basin Gulch. Madison County, dredged in Alder Gulch. Mineral County, dredged and hydraulicked in Cedar Creek. Powell County, hydraulic at Pioneer, Ophir, and Washington Gulch. Granite. Abundant in western part of the State. Jefferson County, quarried at Welch and near Corbin. Lewis and Clark County, quarried at Baxendal, near Helena, also at Helena. Graphite. Beaverhead County, mined near Dillon. Grindstone. Yellowstone County, produced at Columbus. Gypsum. Widely distributed throughout eastern flanks of the Rocky Mountains. Cascade County, formerly mined at Kibby and Riceville. Carbon County, Bridger. Fergus County, mining begun in 1916 at Hanover and development begun near Heath. Jefferson County, quarried near Limespur. Park County, occurs at Hunters Hot Springs. Hematite (red iron ore). Deer Lodge County, found in Cable mine. Jefferson County, with magnetite, in iron mine on Elkhorn Peak, Elkhorn district. Hematite (specularite, turgite). Deer Lodge County, found at Cable mine, carrying gold. Granite County, mined for flux near Philipsburg. Occurs at many localities in Little Belt Mountains district, Cascade, Fergus, and Meagher counties, and prospected at Woodhurst Mountain; in small quantities at other places. Hübnerite. Granite County, occurs at Philipsburg. Madison County, with silver ore in Potosi district, 8 miles southwest of Pony. Powell County, occurs at Sugarloaf Mountain. Silver Bow County, Birdie silver mine and Gagnon and Leonard mines, Butte, small quantities mined. Iron. See Brown iron ore, Hematite, Magnetite, and Pyrite. Lead. See Cerusite, Galena, and Pyromorphite. Lignite. See Coal. Limestone (building). Abundant in western part of the State. Quarried in Carbon County, at Bridger. Flathead County, Kalispell. Gallatin County, Trident. Lewis and Clark County, Helena and East Helena. Silver Bow County, Maiden Rock. Limestone (flux and lime). Cascade County, quarried at Albright and Logging Creek. Gallatin County, Bozeman. Jefferson County, Limespur. Lewis and Clark County, East Helena. Powell County, Elliston. Silver Limonite. See Brown iron ore. Blaine County, with apatite and augite in Black Diamond prospect, Bearpaw Mountains, high grade, not mined. Deer Lodge County, was formerly mined for flux at Cable mine. Gallatin County, near Bozeman. Jefferson County, formerly mined with hematite in iron ores on Elkhorn Peak. Malachite. Deer Lodge County, at Cable mine. Granite County, GraniteBimetallic mine near Philipsburg. Jefferson County, small quantities in Elkhorn mine and McClellan Creek district. Phillips County, found in small quantities in gold-bearing veins near Landusky. Silver Bow County, Butte district and in many other places. Of more mineralogic than economic interest. Manganese ore. Cascade County, manganiferous silver ore mined at Neihart. Deer Lodge County, carries gold and silver at Cable mine. Granite County, was mined in Granite-Bimetallic mine near Philipsburg. Madison County, prospected on Wigwam and Cherry creeks, 15 miles southeast of Virginia City, and in Madison Valley, 7 miles southeast of Norris. Silver Bow County, oxidized ore of Butte mines, silver bearing. See also Psilomelane, Pyrolusite, Rhodonite, and Wad. Marble. Gallatin County, near Manhattan. Lincoln County, near Libby. Marcasite. Deer Lodge County, carries gold at Cable mine. Lincoln County, found in Troy, Grouse Mountain prospects. Silver Bow County, common in Butte mines. Mica (phlogopite). Lincoln County, Rainy Creek near Libby; exceptionally abundant. Molybdenite. Beaverhead County, occurs in quartz veins near Dillon. Cascade County, at Neihart. Granite County, Drummond and at head of Little Gold Creek. Jefferson County, at Homestake. Monazite. Granite County, has been found in black sands at Princeton. Madison County, at Norris. Powell County, locality not reported. Natural gas. Oil. One well in Dawson County at Glendive and two wells in Hill County at Havre, drilled in 1914. See Petroleum. Pearceite. Lewis and Clark Coupty, at Marysville, in the Drumlummon mine, associated with quartz, calcite, and chalcopyrite. Petroleum. Teton County, in northwest part; no production. Phosphate. Granite County, good bed at Philipsburg. Madison County, thin beds in canyon of Jefferson River between Limespur and Cardwell. Powell County, good bed near Elliston, and 6 miles north of Garrison. Silver Bow County, Melrose. Pisanite. Silver Bow County, common in old drifts in Butte copper mines. Platinum. Granite County, rare in black sands at Princeton, not mined. Polybasite. Cascade County, with galena and sphalerite in Neihart district. Lewis and Clark County, rich in silver, Drumlummon mine, Marysville Proustite. Granite County, sparingly scattered through ore in Granite-Bimetallic mine, Philipsburg. Psilomelane. Silver Bow County, at Butte, common surface ore in many veins, usually contains silver. Pyrargyrite (ruby silver). Cascade County, common in Neihart district, usually associated with polybasite. Deer Lodge County, known but not now mined. Granite County, Granite-Bimetallic mine near Philipsburg, with gelena and sphalerite. Lewis and Clark County, Drumlummon mine, Marysville. Pyrite. Common ore of gold, has been mined in the following districts: Broadwater County, Beaver Creek, Crow Creek, Indian Creek, Radersburg. Cascade County, Neihart. Deer Lodge County, Cable. Fergus County, Ford Creek, Giltedge, Maiden. Granite County, Philipsburg. Jefferson County, near Basin, Boulder, Clancey, Elkhorn, Gregory, Warm Spring Creek. Lewis and Clark County, Bald Butte. Lincoln County, Sylvanite. Madison County, Pony. Missoula County, Mineral Point, Mineral Hill, Phillips County, Landusky, Alabama. Powel. County, Elliston. Silver Bow County, Butte (cupriferous). Pyrolusite (black oxide of manganese). Granite County, mined for flux in Flint Creek (Philipsburg) district. Meagher County, large veins at Castle, carry small quantities of lead. Phillips County, with high-grade gold ores in mines near Landusky and Alabama. Silver Bow County, common surface ore in many veins at Butte carrying rhodonite, etc. Usually contains silver and is much sought for as flux for siliceous ores. Pyromorphite (phosphate of lead). Cascade County, found in one mine in Narrow Gauge Gulch, Neihart district. Granite County, in GraniteBimetallic mine, near Philipsburg. Pyrrhotite (magnetic pyrites). Blaine County, found in Bearpaw Mountains. Deer Lodge County, at Cable mine, carries gold. Jefferson County, Elkhorn district. Radium. See Thorianite. Rhodochrosite. Silver Bow County, in silver veins at Butte. Rhodonite (manganese silicate). Silver Bow County, gangue mineral of silver veins of Butte mines, cut as gem. Road metal. See Granite, Limestone, and Sandstone. Sand (building). Dug at many places for local use. Sandstone. Beaverhead County, quarried south of Dillon for building stone, and a variety consisting of nearly pure silica has been used for fluxing and converter lining at the Washoe smelter in Anaconda. Cascade County, quarries at Field and Great Falls. Gallatin County, Salesville and Sappington, near Bozeman. Hill County, at Havre; sandstone suitable for dimension stone is abundant. Park County, Livingston. Yellowstone County, Billings and Columbus. Sapphire. Fergus County, blue gems mined from dike of lamprophyre rock near Yogo Gulch. Granite County, varicolored stones for gems and mechanical purposes mined from placers on Rock Creek, 20 miles southwest of Philipsburg. Lewis and Clark County, mined with gold in placers of Missouri River, east and northeast of Helena, from Canyon Ferry 20 miles down the river. Powell County, varicolored stones for gems and mechanical purposes mined with gold in placers by dredging and sluicing in Dry Cottonwood Creek. Scheelite. Park County, has been mined at Jardine with gold. Silver (native). Cascade County, in oxidized veins in Neihart district. Granite County, in upper levels of Granite-Bimetallic mine, Philipsburg. Jefferson County, at Clancey, Elkhorn, and Ruby mines. Silver Bow County, common in silver veins and oxidized portions of copper veins at Butte. Silver. Predominant metal value in following districts: Beaverhead County, Dillon, Hecla, and Vipond. Cascade County, Neihart. Granite County, Philipsburg. Jefferson County, Elkhorn. Lewis and Clark County, Greenhorn. Park County, Cowles. See also Argentite, Cerargyrite, Pearceite, Polybasite, Proustite, Pyrargyrite, and Stephanite. Specularite. See Hematite. Sphalerite (zinc blende). Broadwater County, mined in Beaver Creek district. Cascade County, occurs with galena in all veins in Neihart district. Deer Lodge County, rare at Cable. Granite County, in all silvergold fissure veins near Philipsburg. Jefferson County, with galena and pyrite and lesser quantities with tetrahedrite in galena ores of Basin, Boulder, Clancey, Elkhorn, Gregory, and Lump Gulch districts. Lewis and Clark County, with galena in Bald Butte, Helena, and Rimini. Lincoln County, Cullahan Creek and Troy. Mineral County, Iron Mountain. Powell County, Elliston. Silver Bow County, common in Butte mines. Spinel (pleonaste). Madison County, between South Meadows and Moore creeks, not mined. Stephanite (brittle silver). Cascade County, rare in Neihart district. Stibnite (sulphide of antimony). Granite County, abundant in primary ore of silver veins near Philipsburg. Tennantite. Granite County, in lower portions of Granite-Bimetallic mine, Philipsburg. Silver Bow County, occurs sparingly associated with enargite in copper veins at Butte. Tetradymite. Broadwater County, with gold and silver in Keating mine, Radersburg. Tetrahedrite (gray copper ore). Granite County, Flint Creek district, with galena and sphalerite, argentiferous; was formerly mined; abundant in lower levels, Granite-Bimetallic mine. Jefferson County, with sphalerite in Elkhorn mine, argentiferous; also at Basin and Clancey. Lewis and |