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Geological Survey DEPARTMENT OF THE INTBKIOB BULLETIN UNITED STATES GEOLOGICAL SURVEY ISTo. ISO SERIES A, ECONOMIC GEOLOGY, I I WASHING-TON GOVERNMENT PKINTING OFFICE 1901 UNITED STATES GEOLOGICAL SURVEY CHARLES J). WALCOTT, DIRECTOR THE OCCUIIRENCE AND DISTRIBUTION CORUNDUM IN THE UNITED STATES BY JOSEPI-I HYDE PR.ATT WASHINGTON G O V JO K N M K N T I' U I M" T I N G O F F I C K 1 \) 0 1 CONTENTS. Pfige. Introduction ..................................................... r ......... 9 Modes of occurrence of corundum ...... ................,_................ U Corundum in peridotites...._ ..... ............ ..................... 1.1 Corundum in biotite, contact on saxonite .............................. 19 Corundum in enstatite. ................................................1. 20 Corundum in serpentine . _.........._....__...........__....-_..--.._.. 20 Corundum in chlorite-schist............... .... ....... ................... 21 Corundum in amphibolite ................................. ........ 21 Corundum (emery) in amphibolite at Chester, Mass......._.--... .. 23 Origin of the emery.....................!.. .................... 25 Corundum in norite .........,........,.....---------.......-...--..-. 26 Corundum in basic minette... _.._...__._ .__.__.._._. .._:__..----_...__. 28 Corundum in andesite............,.........._..............-......... 29 Corundum in syenite ..... ............._..........................,.... 80 Corundum in ampbibole-schist..-.-.'.....,...-.---..-....-......--..... 31 Corundum in gneiss. .........^.....................'. .......^......... 33 Corundum in mica-schist....... .____......___-...__ .,__.__..._......___. 34 Corundum in limestone ........................--.............._..... 36 Corundum in cyanite............................ ..................... 30 Summary of corundum occurrences...... ....... .................... 37 Distribution of corundum .................................................. 37 Sapphire or corundum gems ....... ..-....................._......... 38 Oriental ruby .........--...........'-...'......................-...... 39 Oriental sapphires.................................................. 46 North Carolina sapphires^......... ..........._............. ...... 46 Montana sapphires ........ ......................................... 47 Rock Creek sapphires.........-.-.....-..-..........-...---.... 50 Cottonwood Creek sapphires ...... _........................... 51 Yogo Gulch sapphires ............................. ............ 52 Etching figures............................... ..... .... 54 Corundum ..........-........ ...........;_.............,................ 55 North Carolina..... .... ........................... ................. 55 Macon County .........._. ...........,..-...........-......,.._, 55 Sheffield mine .......... .......... .1...................... 58 Clay County.. ................................................. 58 Buck Creek or Cullakeenee mine.......................... 58 Blue Ridge corundum tracts...................... ......... 59 Jackson County ................ ............................... 61 Georgia .......... .... ...... .-.....:......-......-.......-........... 63 Laurel Creek mine ........................................ 63 Track rock mine ......-......'.......... .................... 65 Foster mine .............. ..._.... .---.-..-............... 65 South Carolina...... ........ .... ........... .... .................. 66 Pennsylvania........'...............-.-........... .......:.......... 66 Montana...___.,......._.... ....................................... 66 5 6 CONTENTS. Distribution of corundum Continued. Page. Emery ........ ........-.....-....--- _.-.._____.___.-._.--..-----.--. 07 Massachusetts._-___.___........_._____._._..____.....-_._--_.-._.. 67 New York....... ...._........ ................................... 70 North Carolina............... ..................................... 72 Methods of mining corundum ...._. .,_._._..___._....__._..--.-.._.-_...-. 72 Methods of cleaning corundum ........................................... 74 Uses of corundum .......... J........................................ ...... 75 Vitrified wheel ..... .................................. ................... 77 Chemical wheel ...................................... ................ 77 Cement wheel ..................... .................................. 78 Other uses..-.-. ................. ....... .............................. 78 Corundum localities in the United States ....._.............-.......--..-. 79 Alabama ........-..-.....'-------..-..---....-.-.---. -..---.----...-..-. 79 California........-..-.--_..._._.-.._-....... ............... .^........... 79 Colorado.................................... .................... ..... 80 Connecticut................................................... ........ 80 Delaware..................... ........................................... 80 Georgia.......-..---..--.-........----...----.---...-..---...-.-..... 80 Maryland .................. r .......................................... .81 Massachusetts ........ ................--...-.....--...--.---.-.......'... 82 Montana .---... ...-.---....-...-...--.-..-.....---........-- '. .......... 82 Nevada ...........-.--.--...--.... ..-----.............---..-..---.....' 82 New Jersey ................ ...._.......-.................-... ......... 82 New York............................................................... 82 North Carolina......._._........-......-.-...... ......_....... ......... 83 Pennsylvania.. .........................'... ........................... 86 South Carolina ....... ......-............................"..... __..... 87 Utah.......:.....'.................. ..,...._...._._-_.---.......... 87 Virginia .............................^............................ 87 Alaska . ................................... .......................... 88 Corundum localities in foreign countries ....'--.---...-.......-..-.-....... 88 Canada .;................. ....^.......................................... 88 India....---..--.-...................................................... 89 Turkey........... .. .......................__._..._....__....._..._.__ 91 Grecian Archipelago .................................................. 91 Other localities.............:....-.-....-......-...-..-..-.-...-.-..-.. 91 ILLUSTRATIONS. Page. PLATE I. Outcrop of peridotite at Buck Creek, Clay County, N. C......... 10 II. A, Bed of ruby-bearing gravel at Caler Fork, Cowee Valley, Ma- con County, N. C.; B, Ruby mine at Cowee Valley, N. C.. with plant for washing the gravels in the foreground............... 40 III. Ruby crystals from Cowee Valley, Macou County, N. C............ 42. IV. Map showing location of sapphire deposits in Montana . ........ 46 V. Sapphire crystals, from Yogo Gulch, Fergus County, Mont ...... 52 VI.i Map showing location of the peridotite rocks and corundum lo­ calities of North Carolina and Georgia ........... ........... 54 VII. General view of the peridotite formation at Corundum Hill, Ma- con County, N. C... .. ...... ................................. 56 VIII. The <; Big vein " at Corundum Hill, between the peridotite and gneiss, Macon County, N. C. ... ......................... ...... 56 IX. Upper end of big cut at Corundum Hill mine, Macon County, N.C...... ................................................:. r ss X. Open cut on a dunite vein at the Mincey mine, Macon County, N.C......................... ................................ 58 XI. A, General view of the Buck Creek corundum mine and peridotite formation, Clay County, N. C.; B, Dunite vein of corundum in the peridotite formation at Buck Creek, Clay County, N. C.. 60 XII. Open cut on peridotite-gneiss contact at Laurel Creek, Georgia, with shaft house in foreground............................ ..... 64 XIII. A, Peridotite formation at Laurel Creek, Georgia; 7:?, Dunite vein of corundum at Laurel Creek, Georgia..................... .. 66 XIV. .4, Corundum mill at Cullasagee, Macon County. N. C.; B, Inte­ rior view of corundum mill at Cullasagee, Macon County, N. C . 74 Fig. 1. Ideal cross section of a corundum contact vein at the Corundum Hill mine, Macon County, N. C -.....-.........................._ 18 2. Ideal cross section of a corundum-dunite vein at the Corundum Hill mine, Macon County, N. C .................. ... ........ .. 15 3. Ideal vertical cross section of a mass of peridotite soon after its in­ trusion in gneiss ..........;........................ ........... 16 4. Ideal vertical cross section showing a somewhat gradual transition from corundum to peridotite...:..............'................... ' 17 5. Map of the Buck Creek peridotite area, showing the relation of the amphibolite dikes........ ............. ..... ................... 22 6. Ideal vertical cross section of corundum in amphibolite at Hunters, Iredell County, N.C.......: ........... '. ......... ............. 7. Corundum crystal showing concentric hexagons on basal plane .... 7 8 ILLUSTRATIONS. Page. Fig. 8. Spokane Bar sapphire deposits, Lewis and Clarke County, Mont.... 48 9. Sapphire crystals from Missouri River bars, Montana ............. 50 10. Map of the peridotite formation at Corundum Hill, Macou .County, N.C....................... .'..................................... 56 11. Map of the peridotite areas in the vicinity of Sapphire, Jackson County, N. C., showing the location of the different corundum mines ..................... ........... ....................... 62 12. Map of the peridotite formation at Laurel Creek,
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