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Show Bonanza Shoot of Gold Quartz at National, Nevada Single Ore Shoot Has Yielded About $4,000,000. Ore Averages 30,000 a Ton During the four years following 1908 n single ore shoot nt National, Nevada, a previously llttlo known mining d strict, yielded about $4,000,-000 $4,000,-000 in gold nnd Is ono of tho most re-mnrknbio re-mnrknbio nnd Interesting bodies of high grndo ore discovered In the west. Tho district lies on tlio wostorn slopo of Santa Rosa Rnngo ln Humboldt county nenr tho Oregon Stnto lino. Tho mineral deposits of this range, llko tlioso of mnny othor pnrts of No- Vndn. mnV llO llll-Mml Intn turn nrln. uuu, iuujt uo uiviuca mio two principal prin-cipal clnssos, younger gold and silver sil-ver bcnrlng veins that ociur In or near tho Tertiary volcanlco rocks and much oldor gold nnd silvor bearing bear-ing veins that occur in sedimentary and associated granlt'c rocks. In this area tho older deposits aro but poorly poor-ly represented and havo yielded only n small out put,, but ono of the younger young-er or Tertiary volns has locally been wonderfully rich yielding much ore averaging $30 a pound. During tho early porlod of activity a few thousand thous-and tons of low grade ore, assaying about $100 n ton, wero thrown on tho dump of tho National mlno, but tho oro shipped nvoraged nbout $30,000 n ton In gold having n valuo of $10.60 an ounce, tho remainder being silver. sil-ver. Tho volns nro Inclosed In latlte, rhy-ollto, rhy-ollto, basalt, basalt tuff, nnd trachyte. Thoy onsIst of shenred rock a few foot wldo traversed by fluartz, seams containing stlbnlto, pyrlto, chnlcopy-rlto, chnlcopy-rlto, nrsenopyrlto, zinc blende, nnd galena. C'nnabar was found n ono of tho volns. Most of tho volns that carry much stlbnlto aro poor ln gold and silver. Nntlvo gold Is found principally prin-cipally In tho rich shoot of the National Na-tional vein tho Isolated position of which, In a district of quartz stlbnlto veins poor in gold and silver, is remarkable. re-markable. Tho sevoral veins appear to belong to ono and tho samo epoch of niterallzatlon, tho gold shoot being be-ing a .local development upon ono of tho normal stlbnlto volns. The gold Bhoot was encountered 40 feet below tho surface and has been followed on the dip of the vein for 800 feet, tho stone length reaching 250 feet. The oro, which ran $20 to $30 to tho pound ocurred mostly ln an Irregular foot wall seam from a few Inches to a foot wide. Tho veins wero formed at a depth of 1,000 to 2,700 feet below tho sur- faCQ bv hot napfnillni- nnllltlnna nrnh. nbly of a composition somewhat like that of Steamboat Springs In Nevada or the silica sodium wators of the Yellowstone National Park. Tho National mining district has recently boon described by Wnldcmar Llndgron, whoso report, Bulletin 601, may bo obtained free from tho Director, Direc-tor, U. S. Geological Survey, Washington, Wash-ington, D. C. |