Natron. In Lake County, in lakes and ponds. Natural gas. Malheur County, occurs in several wells near Vale and Ontario; not commercially developed. Nickel. See Garnierite, Genthite, and Josephinite. Niter (saltpeter). Lane County, ledge near Mount June; also in marsh deposits of southeastern Oregon. Olivine. In black sand in Baker County, Durkee. Clatsop County, Astoria, Carnahan station, Clatsop Spit, Elk Creek, Fort Stevens, Gearhart Beach, Hammond, Morrison, Seaside, and Warrenton. Coos County, Johnson Gulch, Randolph district (in old and present beach sand), and Whiskey Run. Curry County, Chetco, Eckley, Gold Beach, Port Orford, and Rogue River beach. Josephine County, Holland, Kerby, and Wolf Creek. Multnomah County, Fulton and Latourell Falls. Polk County, Falls City. Umatilla County, Weston. Wasco County, Hood River beach. Also in other places. Opal. Baker County, abundant in tuff a few miles below Durkee; has been mined. Clackamas County, in seams in trap rock forming falls at Oregon City. Gilliam County, Hay Creek. Grant County, Grub Creek, near Canyon City. Umatilla County, 4 miles above Weston, on Pine Creek. Wasco County, The Dalles, and near Antelope. Platinum. Principal production from beach sands in Coos County, near Bullards, and at Bandon, Randolph district, and Whiskey River, and in Curry County, near Port Orford, Cape Blanco, and Ophir, upper Sixes River, Gold Beach, and in placers of Rogue River. Occurs in black sands in Baker County, at Buck Gulch and Durkee. Douglas County, Drain, Glendale, and Riddle. Grant County, at Griffith mine. Josephine County, Galice, Waldo, and Greenback districts, and elsewhere; in black sand at Browntown, Grants Pass, Illinois River, and Kerby district. Linn County, Foster. Union County, La Grande. Wheeler County, Antone. Priceite. Curry County, on coast 5 miles north of Chetco. Proustite. Baker County, Sumpter district. Pumice. Klamath County, abundant west of Crater Lake. Pyrargyrite. Baker County, mined in Elkhorn, Sumpter, and Rye Valley districts. Grant County, Granite district. Pyrite. Found in nearly all mining districts of Baker, Grant, and Union counties. Curry County, in gold veins of Mule Mountain district, Wakeup-Riley Ridge, and Illinois River 2 miles north of mouth of Collier Creek. Douglas County, Roseburg district; has been mined in Bohemia district. Jackson County, mined for gold at Ashland, Gold Hill, Jacksonville, and Upper Applegate district, and Braden, Opp, and Tin Pan mines, Grants Pass district. Josephine County, Queen of Bronze mine near Waldo; Greenback, Baby, Silent Friend, and Orofino mines, Alameda mine, Galice district, Grants Pass, and Lower Applegate district. Lane County, has been mined in Bohemia and Blue River districts. Occurs in all districts of the Cascade Mountains north of Bohemia. Pyrolusite. Baker County, occurs in Sumpter district; Jackson County, Ashland and Gold Hill districts; Josephine County, Cave Creek in Waldo district. Pyrrhotite. Baker County, Sumpter district; Virtue district, carries gold. Douglas County, Cow Creek Canyon. Jackson County, Braden and Jewet mines, Grants Pass district, and Corporal G mine, Upper Apple gate and Gold Hill districts. Josephine County, Queen of Bronze mine near Waldo; Galice and Grants Pass districts. Quicksilver. See Cinnabar. Rhodochrosite. Josephine County, Waldo district on Cave Creek, 3 miles below Oregon Caves on trail down Cave Creek. Rhodonite. Josephine County, Waldo district on Cave Creek, 3 miles below Oregon Caves on trail down Cave Creek. Road metal. See Basalt and Sand and gravel. Salt. Douglas County, Salt Springs, north of Roseburg. Lake County, reported abundant in numerous marshes and lakes. Sand and gravel. Dug at following places: Benton County, Corvallis ; Klamath County, Klamath Falls; Lane County, Eugene; Linn County, Albany; Marion County, Salem; Multnomah County, Portland and St. Johns. Sandstone. Has been quarried locally in Benton, Clackamas, Coos, Curry, Douglas, Jackson, Lane, Lincoln, Polk, Union, Washington, and Yamhill counties. The use of cement has led to the suspension of operations in many places. The largest quarries are at Oakland, Douglas County, and at Pioneer, Lincoln County. Sapphire. Harney County, secs. 1, 6, and 17, T. 25 S., R. 35 E. Siderite. Josephine County, Galice district. Grant County, Sumpter district. Crook County, Trout Creek mines. Jackson County, in fractures of greenstone 2 miles north of Watkins, Ashland district in Baron mine, and 30 miles east of Medford. Lane and Douglas counties, in Bohemia district. Sylvanite. Baker County, occurs in quartz vein at Bryan mine, Cornucopia district. Josephine County, Grants Pass district. Talc. Clackamas County, Eagle Creek. Jackson County, near Woodville. Josephine County, Grants Pass. Tenorite. Josephine County, oxidized ore in Queen of Bronze mine, Waldo district. Tetrahedrite. Baker County, Cable Cove, Greenhorn, Sumpter, and Virtue districts. Grant County, Susanville district, small quantity in Badger mine. Tetrahedrite (mercurial, schwartzite). Baker County, occurs in Sumpter district. Thomsonite. Lane County, in road cut 100 yards west of Deerhorn. Tuff (rhyolitic). Common in lake beds and a recent surface cover in Baker and Grant counties. Baker County, quarried for building stone at Pleasant Valley; also in Grant County and many other places in eastern Oregon. Volcanic ash. See Tuff. Wad. Baker County, Sumpter district. Wood (silicified). Of some use for ornamental work. Abundant in Wil- Zinc. PENNSYLVANIA. Allanite. Chester County, at Bethlehem, in East Bradford and Coventry townships. Lawrence County, Princeton. Lehigh County, at Allentown. Philadelphia County, Frankford. Nearly all localities are granitic rock. Almandite. See Garnet. Amethyst. Bedford County, reported at East Bedford. Chester County, Pocopson, Sadsbury, and East Bradford townships. Delaware County, 1 miles northeast of Media, at other localities in Upper Providence, Middletown, and Astor townships. Huntingdon County, Birmingham. Philadelphia County, Falls of Schuylkill, Rolandsville; a few stones suitable for gems. Anthracite. See Coal. Apatite. There are no commercial workings, but some of the chief localities are: Chester County, at Penn's Meetinghouse. Delaware County, at Leiperville, near Chester. Philadelphia County, in several quarries in Frankford, Germantown, and West Philadelphia. Asbestos (amphibole). Delaware County, formerly mined near Rockdale, occurs at Mineral Hill, near Media. Asbestos (chrysotile). Adams and Franklin counties, small veins in greenstone in the South Mountains. Delaware County, has been found in Marble, Radnor, Upper Providence, and other townships. Northampton County, at Easton. Azurite (blue carbonate of copper). Berks County, Fritz Island, near Reading, sparingly with copper ores and magnetic iron ore; Chester County, Wheatly mine near Phoenixville. Lebanon County, Cornwall, with chalcopyrite and malachite in magnetic iron ore. Montgomery County has been mined at Perkiomen and Eaton mines, at Audubon (formerly Shannonville), Upper Salford Township, near Sumneytown. Barite (heavy spar). Bucks County, occurs west of New Hope, in several old Beryl. mines. Chester County, in small quantity in Wheatley, old Jug Hollow, and other mines near Phoenixville, Schuylkill Township. Franklin County, mined to a small extent near Chambersburg and Waynesboro. Fulton County, formerly mined at Fort Littleton. Montgomery County, at the Perkiomen and Eaton copper mines, Marble Hall, Mogees, North Wales, Sanatoga. Other small occurrences. Barite is not mined on a commercial scale in Pennsylvania at present. Chester County, Union Township, near Northrop and Unionville, has yielded hundreds of pounds of crystals. Delaware County, Deshong's quarry at Leiperville; the Shaw-Ezra quarry at Chester; Avondale quarry near Media; many localities in Concord, Marble, Middletown, and Upper Province townships; Linwood, occasionally found. Philadelphia County, Fairmount Park, Germantown, Logan, Mount Airy, and Shawmont have all produced gem specimens. Bluestone. See Sandstone. Bornite. Montgomery County, formerly mined at Ecton mine, near Audubon, at Hendricks, Schwenksville, and Sumneytown. Philadelphia County, found at Frankford and quarries in Germantown. Bromine. Allegheny County, concentrated from brine at Pittsburgh. See also Salt. Brown iron ore (limonite). Extensively developed in the Great Valley from Delaware River to the Maryland line. Many scattered ore banks have been worked out in Berks, Cumberland, Dauphin, Franklin, and Lebanon counties. Occurs in Chester and Montgomery counties in a narrow belt crossing the Schuylkill at Spring Mill. Bedford, Huntingdon, and Mifflin counties, occurs in Juniata region. Blair County, in Yellow Creek district. Lancaster County, in the Chestnut Hill and other ore banks. Middle Pennsylvania, in Kishacoquillas, Nittany, Morrisons Cove, and Sinking Canoe valleys. Juniata and Perry counties on the affluents of the Juniata. York County, irregular masses scattered through clay near Dillsburg, mined at Heck mine. Western Pennsylvania: Armstrong County, formerly worked in West Franklin Township; also occurs in Beaver, Butler, Clarion, Center, Clearfield, Jefferson, Indiana, and Lawrence counties. See also Mineral paint. Brucite. Berks County, at Fritz Island, near Reading, and near Sinking Spring, Spring Township. Lancaster County, southern part, at New Texas, in Wood's mine, near Lyles post office, in large plates or masses, and in crystallizations several inches across; at Low's mine, with hydromagnesite. Cadmium. See Greenockite. Calamine (zinc silicate). Chester County, Wheatley and other mines near Phoenixville. Columbia County, Espy. Lancaster County, Lancaster. Lehigh County, Friedensville, Saucon Valley, with blende in limestone. Montgomery County, Eaton mine at Audubon. Carnotite. Carbon County, in conglomerate on Mount Pisgah, three-fourths of a mile north of Mauch Chunk. Cement material. Pennsylvania leads all the States in production of Portland cement. Its output in 1914 was 26,570,151 barrels. There are 20 or more plants in the Lehigh district and other plants at York, Pittsburgh, Newcastle, and Wampum. Limestone and shale suitable for cement making are abundant throughout the State. Rock is quarried for cement in Berks County, at Evansville and was long quarried at Molltown. Lawrence County, at Newcastle and Wampum. Lehigh County, Allentown, Cementon, Coplay, Egypt, and Fogelsville. Northampton County, Bath, Martins Creek, Nazareth, Northampton, Siegfried, and Stockertown. Blast-furnace slag and limestone are used at Pittsburgh, Allegheny County, for Portland cement. Clay dug at Mines, Blair County, Mount Holly Springs, Cumberland County, and at Saylorsburg, Monroe County, is used for white cement. Cerium metals. See Allanite. Cerusite (lead carbonate). Bradford County, in Carpenter mine, near New Albany. Chester County, in small quantities at Phoenixville lead mines, Schuylkill Township. Lancaster County, Lancaster. Montgomery County. Ecton copper mines, Lower Providence Township. Chalcocite (copper glance). Chester County, in small quantity at Phoenixville lead mines, Schuylkill Township. Lancaster County, Woods mine, Little Britain Township. Montgomery County, Perkiomen copper mines, Lower Providence Township, near Sanatoga and many other places in the Triassic shale. Philadelphia County, Frankford and Rolandsville. Chalcopyrite (copper pyrites). Berks County, formerly mined at Jones mine and at Fritz Island mine near Reading. Chester County, Wheatley lead mine, Phoenixville, French Creek iron and copper mines, Warwick Township. Found only in small quantity in Delaware County, Avondale quarries. Lancaster County, Gap nickel mine. Lebanon County, occurs with other copper ores and is mined with magnetite at Cornwall, elsewhere unimportant as an ore. Montgomery County, in Lafayette soapstone quarry; has been mined in Sassamansville, Sumneytown, Ecton, and |