 | | Report (issue) | | DESCRIPTIVE MINERALOGY OF PENNSYLVANIA 104 Na 2Al 2 Si3 Oi .2H 2 O; SiO 2 47.4, A1 2 O 3 26.8, Na...Na 2 O 16.3, Lenni, Delaware County. Crystals. Eyerman, 1911, 11. Composition: Analysis: Fe 2 O3 CaO...Sp.gr LOCALITIES: Berks County: Birdsboro, and Gickerville; Delaware County: Leiperville, Lenni (druses...colorless crystals), Felton's farm (Chester), and Ward's quarry; Montgomery County: Sumneytown, and Perkiomenville...100. Analysis: Railroad cut east of Reading (probably Birdsboro), Berks County. White, Smith, 1910, 540 |  | | Book (edition) | | LAZULI TURQUOISE GARNET ONYX • PERIDOT* • ZIRCON • CARNELIAN TOURMALINE OPALS • AOATI • ...Science and Mechanics publishing 4^0 company East Ohio Street Chicago 11, Illinois Copyright 1951...SPINEL STAUROLITE •^^ VESUVIANITE WILLEMITE ZIRCON CRYSTALS Crystal forms 5 velopment of one face... areas of the east and west, and the plains between The mountain regions in the east from Maine down...Others have washed out of the rock formations of the east and west coast mountains, and the diamonds of the |  | | Book (volume) | | ASHTABULA COUNTY CONNEAUT, area pits, quarries, rd. cuts, etc.⎯cone-in-cone Calcite. CLERMONT COUNTY MILFORD...CLINTON COUNTY WILMINGTON, area of Todd’s Ford, a mineral deposit⎯Hematite. COSHOCTON COUNTY AREA, townships...CUYAHOGA COUNTY CHAGRIN FALLS (on Geauga Co. line), area quarries⎯oilstone. DELAWARE COUNTY DELAWARE...nodules⎯Pyrite (crystals sharply cubic). FRANKLIN COUNTY COLUMBUS, area countywide exposures of blue clay...HIGHLAND COUNTY SINKING SPRING, area ore deposit (most important in Ohio) ⎯Hematite. HOCKING COUNTY AREA |  | | Book (volume) | | ASHTABULA COUNTY CONNEAUT, area pits, quarries, rd. cuts, etc.⎯cone-in-cone Calcite. CLERMONT COUNTY MILFORD...CLINTON COUNTY WILMINGTON, area of Todd’s Ford, a mineral deposit⎯Hematite. COSHOCTON COUNTY AREA, townships...CUYAHOGA COUNTY CHAGRIN FALLS (on Geauga Co. line), area quarries⎯oilstone. DELAWARE COUNTY DELAWARE...nodules⎯Pyrite (crystals sharply cubic). FRANKLIN COUNTY COLUMBUS, area countywide exposures of blue clay...HIGHLAND COUNTY SINKING SPRING, area ore deposit (most important in Ohio) ⎯Hematite. HOCKING COUNTY AREA |  | | Journal (article/letter/editorial) | | U-Pb garnet and titanite age for the Bristol Township lamprophyre suite, western Abitibi Subprovince...garnet. The gametite dlke is part of the Bristol Township lamprophyre suite, which is extremely enriched...for Archean rocks (e.g., Davis 1982; Krogh 1982). Zircon, titanite (sphene), baddeleyite, and monazite are...geochronology, and structural history The Bristol Township lamprophyre suite is located 25 km west-southwest...porphyry intrusions at 26962688 Ma (age ranges from zircon U-Pb data, with 2u errors of + 2 to k 4 Ma). In |  | | Report (volume) | | geologic map and section of the area between Willowdale and Ashwood_____________-___-___-____-_-___-----_...drainage divide between the John Day River on the east and the Deschutes and Crooked Rivers on the west...however, and the higher parts of the country south and east of Ashwood are forested with yellow pine. A reconnaissance...as Eocene on the basis of fossil plants collected east of the Antelope-Ashwood area at localities on Cherry...trachyandesite (Peck, 1961). In the area between Willowdale and Ash wood (pi. 1), the formation is about |  | | Book (volume) | | This rectangular Great Plains state rises 4,460’ east to west, from 840’ to 5,300’, yet so imperceptibly...in Dawes Co. and the rather extensive rock beds east of the Orella railroad sta. ranks among the finest...chalcedony, jasper and gem petrified wood. BUFFALO COUNTY KEARNEY, area gravel bars and pits along the Platte...townagate, chalcedony, jasper, petrified wood. CASS COUNTY WEEPING WATER, SE, on rd. to Nehawka, in the Snyderville...chalcedony, jasper, fossils. CHERRY COUNTY VALENTINE, in the Sandhills county along the Niobrara R. and Minnechaduza |  | | Report (volume) | | ........................................... Pennsylvania...............................................value. Some minerals, such as the copper ores of Pennsylvania, are included in the list not because they occur...and Ehrenfeld, Frederick, Minerals of Pennsylvania: Pennsylvania Top. and Geol. Survey Comm. Kept. No...See Bauxite and Halloysite. Asbestos. Tallapoosa County, with corundum deposits near Dudleyville; not found...commercial quantity or quality. Asphalt. Colbert County, small quantity has been shipped from near Leighton; |  | | Report (volume) | | Geology of the Wood and East Calhoun Mines Central City District Gilpin County, Colorado GEOLOGICAL SURVEY... Geology of the Wood and East Calhoun Mines Central City District Gilpin County, Colorado By AVERY A. DRAKE...vein ______.-___-_-_____-____.____-_-_______-_ Willowdale vein___________--____________-_----____-__-__...of the East Calhoun mine. 13. Geologic map of the Wood crosscut and drift, sixth level, East Calhoun...Calhoun mine. 14. Geologic sections of the East Calhoun mine and detailed section of the Wood 520 raise. 15 |  | | Journal (article/letter/editorial) | | OREBODY WITH VOLCANIC ONTARIO, AS INFERRED FROM ZIRCON U-Pb AGES* P. D. NUNES** Departmentof Mineralogyand...lowersupergroup and *** Present Address: 157 Burbank Drive, Willowdale, Ontario M2K 1N9, Canada. the entireuppersupergroup...metal mineralization in the Timmins-Matachewan Township(sampleN77-16); (8) plagioclase-bearing area, one...21); and (4) calc-alkalinerhyolitebrecciaon the east relatedto the contactof the two supergroups. sideof...sideof the Kidd Creek mine openpit in Kidd Township (sampleN77-22). The relative agesof samples Geochronology |  | | Journal (issue) | | the advice of Dean Edward H. Kraus and Professor Chester B. Slawson of the University of Michigan, who were... THE TOURMALINES OF THE PALA VALLEY, SAN DIEGO COUNTY, CALIFORNIA, U.S.A. By M. J. O'DONOGHUE, M.A.,...north-west San Diego County, about 45 miles north of San Diego and 80 miles south-east of Los Angeles. It...bearing pegmatites of the Pala District, San Diego County, California. California Division of Mines, Special...Fig. 8. Fig. 10. Ruby. Tourmaline. Fig. 12. Zircon. Fig. 14. Diamond. J.Gemm., 1979, XVI, 5 305 |  | | Journal (article/letter/editorial) | | have been donated by Pappy's Beryl Shop, Rt. 6A, East Hampton, Conn. The xls average 1 inch in length...quartzite has been found in Shahan's gravel quarry, east of U.S. 113A, 3 miles south of Dover, Kent Co.,...metagraywacke along the county road half way between Chestnut Gap and Lebanon School, Fannin County, Ga. These crystals...aluminum silicate rocks. This area is in Clearwater County, Idaho, and any visiting rockhounds can get directions...turn right and where black top turns left keep on east on country road and in about 2 miles you will reach |  | | Journal (article/letter/editorial) | | is anomalously molybdenum enriched. A new U-Pb zircon date on this mineralized porphyry fixes its emplacement...Radiometric ages were determined using conventional U-Pb zircon geochronological methods by F. Corfu at the Jack...mine in Tisdale township, 13 km northeastward to the Hoyle mine in Whitney township (Fig. 1). This belt...are older than the Timiskaming strata in Whitney township. Stratigraphic relationships and description Figure...section at the Pamour 1 and Hoyle mines in Whitney township (Aitken, 1990; Kusic and Olson, 1990; West et |  | | Book (edition) | | describes sites under of the nearest town and county. and the many maps included book contain such...intersect at right angles. The crystals, such as zircon, commonly have a square cross-section. The hexagonal... (^h /&> ^& \b^ ^ VESUVIANITE WILLEMITE ZIRCON CRYSTALS How 10 / gem to identify minerals...crystalline. Some, such as the diamond and zircon, are outstand- depends on refractive index, the...lie in the range between opal (sp. gr. 2.1) and zircon (sp. gr. 4.7), quick and accurate determinations |  | | Journal (article/letter/editorial) | | lower greenschistfaciesmetamorphism produced a major east-west-trending, south-facingrecumbent anticline (F•)...interior of the intrusion are >5 (4.88, cessory zircon. 5.65-7.32; Table 2). Hence, this lithology cannot...Accessorymineralsinclude sphene,allanitc, apatite,trace zircon, and occasionalprimary zoisite.Examination of drill...aplitetrendtraverseseoherently were removedin spheneand biotite, zircon and alfrom the granodioritefield to the monzogranite...levels.Below the aplites, Mink Lake stockoccursin an east-west-trending mineralization dies out into barren |  | | Journal (article/letter/editorial) | | chemical,and isotopicfeaturesobservedin the part of the east-trending, Schreiber-WhiteRiver secdeposit.The U-Pbstudiesby...1, The greenstone belt is foldedinto the broad,east- Figs.1 and2). The CedarCreekstockseemsto be a trending...similarfragments hasalsobeenrecog- unit 7f). nized to the east on the Teck-Coronaproperty Subunit7a2 consistsof...SL= sphalerite, SP= sphene, TR = tourmaline, ZR = zircon tion in subunit763 israre, althoughup to 20 percent...portionsof the percent poikilitic quartz, mica, zircon, and very schists.Garnetslocallyexhibitpoikiloblastictextures |  | Burrows, D. R., Spooner, Edward T. C., Wood, P. C., Jemielita, R. A. (1993) Structural controls on formation of the Hollinger-McIntyre Au quartz vein system in the Hollinger shear zone, Timmins, southern Abitibi greenstone belt, Ontario. Economic Geology, 88 (6) 1643-1663 doi:10.2113/gsecongeo.88.6.1643 | Journal (article/letter/editorial) | | Theserelationshipshaverecentlybeenconfirmedby U-Pb zircon dating(Corfuet al., 1989) whichclearlyshowsthat...Group(youngersediments; and form a belt extendingto the east Althoughthismodeldoesnot yieldfully satisfactory...(1982) identified north-southfolds refolded about east-northeast axeswith later superimposed shearingassociated...(Fig. 1). Davies (1977), on the otherhand,suggested east-west foldingmodifiedby a sinistralcoupleactingin...Hollinger fault during this study and 60ø to the east(Figs. 1 and 2). As discussed in showednormaldisplacement |  | | Journal (article/letter/editorial) | | the shear zone, mainly in the segment that trends east-southeasterly where deformation is stronger. The...Alkalic Complex (Proterozoic) Fault 2688 Ma U-Pb zircon age Headframe: Hemlo gold deposit FIG. 1. Simplified...(area of Fig. 2). Modified from Muir (1997); U-Pb zircon ages from Corfu and Muir (1989a) and Jackson et...gneissic phase of the Pukaskwa complex yielded an U-Pb zircon age of ~2719 Ma, whereas an internal phase of the...pluton and the Cedar Lake pluton, yielded U-Pb zircon ages of ~2688 Ma. The Cedar Creek stock has been |  | | Journal (article/letter/editorial) | | Ontario,Canada, in MacDonald, A.J.,ed.,Gold'86:Willowdale, Ontario, Detailedstructural interpretation thekeyto...consistent withthezircondates.Thepre- occurs cise zircon date of 2699 Ma from the Trout Lake batholith ...andmetalassociations, all suggest a near-sur- Willowdale,Ontario,KonsultInternational Inc., p. 137-148...Ontario,Canada, in Macdonald, A.J.,ed.,Gold'86:Willowdale, Ontario, Sillitoe,R.H., Hannington, M.D., andThompson |  | Pan, Yuanming, Fleet, Michael E., Stone, William E. (1991) Skarn mineralization (Cr, Fe, Au) in an Archean greenstone belt, White River Property, Hemlo area, Ontario. Economic Geology, 86 (8) 1626-1645 doi:10.2113/gsecongeo.86.8.1626 | Journal (article/letter/editorial) | | northeastshoreof Lake Superior,approximately 35 km east of Marathon, Ontario, Canada (Fig. 1), containspublishedreservesof...++ + + + + + ++•+++ km I I + + + + + + USA + + + + +++ + + + 0 ++++4.+++ •' + + + + +...Riverpropertyof LAC MineralsLtd. is part of the east-west-trending Hemlo-Heron Bay belt in the Wawasubprovince...as monazite,REE-bearingclinozoisite,apatite,and zircon (Pan and Fleet, 1990). Most of these epidoteprehniteveinscut...proximityto lithologicboundariesandbrit- to the east of the study area. Again, this skarnlike tle-ductile |  | | Report (issue) | | thick in Paulina Basin (Davenport, 1971) and to the east in the Suplee-Izee area (Dickinson and Vigrass,...1978, The age of the "Pilot Rock flora," Umatilla County, Oregon [abs.]: Geological Society of America Abstracts...Bedrock geology of the Mitchell quadrangle, Wheeler County, Oregon: Oregon Department of Geology and Mineral... D.A., 1969, Reconnaissance geologic map of the east half of the Bend quadrangle, Crook, Wheeler, Jefferson...L., 1944, Contribution to the geology of Latah County, Idaho: Geological Society of America Bulletin |  | | Book (volume) | | references, among them may be mentioned: Vermont, Pennsylvania, North Carolina, Oregon, Kansas, Alabama, Ohio...Kobuk jade locality. Descriptions of San Diego County, California, gemstones and the mines in which they...the generous assistance of many residents of that county. My special thanks are extended to Elbert H. McMacken...Cassiterite, Diaspore, Enstatite, Hypersthene, Zircon, Algodonite and Domeykite, Sphalerite, Niccolite...cassiterite mass 122. A diaspore crystal 123. A zircon crystal 124. A sphalerite crystal 125. A sphalerite |  | Leitch, C. H. B., Godwin, C. I., Brown, T. H., Taylor, B. E. (1991) Geochemistry of mineralizing fluids in the Bralorne-Pioneer Mesothermal gold vein deposit, British Columbia, Canada. Economic Geology, 86 (2) 318-353 doi:10.2113/gsecongeo.86.2.318 | Journal (article/letter/editorial) | | coas,.,u,o.c co..,ex c.c co • I • BR • z=zircon u=U-Pb ••1 0 \\ 319 • • • • •+ + + + +...the west and the Intermontanesuperterrane on the east (Monger, 1984). Potter (1986) andRusmore(1987) proposedthat...still containssome 150,000 Slickensides plunge 45 ø east and stepsindicatethe last movementwas reverse.Major... Canada, in Macdonald, A. J., ed., Gold '86: Willowdale, Ontario, KonsultInternat., p. 3-26. bonicfluidwith...Zimbabwe, in Macdonald,A. J., ed., Gold '86: Willowdale, Ontario, KonsultInternat., p. 255-269. Fyfe |  | Arehart, Greg B., Foland, K. A., Naeser, C. W., Kesler, Stephen E. (1993) 40 Ar/ 39 Ar, K/Ar, and fission track geochronology of sediment-hosted disseminated gold deposits at Post-Betze, Carlin Trend, northeastern Nevada. Economic Geology, 88 (3) 622-646 doi:10.2113/gsecongeo.88.3.622 | Journal (article/letter/editorial) | | similartextureandcomposition acrossthe valley to the east in Little Boulder basingavea K/Ar dateon biotiteof...is Zircon and Apatite FissionTrack Results Althoughthe fissiontrack annealingpropertiesof zircon are...uranium contents and fissiontrack agesof individual zircon grainsfrom rocksthathavebeenmoderatelyheated.The...nearlyallofthesericitefromthissample of apatiteand zircon (Fig. 4, Table 4). All of these appearsto be detrital...detrital.The apparentageof the seri- samples contained zircon,but onlyone(POD-1)conciteconcentrate fromthissampleis84 |  | | Journal (article/letter/editorial) | | Quebec. It occurswithin the northeasternpart of the east- tet-Troilusarea was in 1958 with the discoveryof...overlainby moremaficandlamiboundedto the southby an east-west-trending fault natedlapillituffs.Thesetuffsdisplaya...vations of diamond drill core, a limited amount of east. thin sectionexamination andby interpretation of...Ontario,Canada,in Macdonald,A. J., ed., Gold '86: Willowdale,Ontario, KonsultInternat., Inc., p. 340-354....Macdonald, A. J., ed., Proceedings of Gold'86, Willowdale, Ontario,KonsultInternat., Inc., p. 327-339. |
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