Show SEVEN DEVILS IDA I Conclusion of a Review of the Miner alization of That Jtegion nlzntan gOJ I On March 3rd The Tribune printed an article on the mineralization of the I Seven Dovlls country which was writ r I ten by Piof Marcus E Jones of this city well known as a leading expert The second und concluding part of the I review of that region appears herewith i here-with from Prof JoneVa pen Both articles are well worthy to be not only read with attention but to be ore served ay a comprehensive practical 1 and sclunllflc statement of facts and conditions On Hornet creek just above Days the quartx porphyry which passes on 1 I the eastern side of the Cuddy mountains I moun-tains tucms to occur again but Is I mostly covered up by i basalt At this polnl there arc a number of veins of I Iron Impregnated with corpel and carrying car-rying a little silver The widest of these Is aboul fourteen feet The veins scam lo have the general direction of i I all the others and lie In series As you go westward they lie wholly in the I granite I and all iarry some gold Be rause of he 1 flatness of the t country and the presence of waler close to the surface they have been worked but Illeel After we pass over the divide loading to the Snake we find no more viin exposures ex-posures till we reach Cuprum since the I whole country is covered with basalt Here the basalt cap has been eroded I so as to expose the schists again Just j I back norlh of Cuprum there is a muss of Intruded 1 rock called I dlorlti I but which differs bul Ill from the usual I eruptive rocks of the region This siiins lo extend cast nnd wist at least it runs up the ridge toward llni granite I and hohisl contact A llltlc I I I work has boon done on It for there urc many small gaslu veins In It I which dip nearly vertically and run in various directions These veins are very rlrh In copner but sire so imrjtow as to bu unuorlcablc After going down urme distune they are cut off by a hange of formation which would lead lo the supposition that the socalled diorite Is simply a surface flow Some distance below Cuprujn there Is i quite an area of limestone which Is clearly not inlerstratinud with tho schist but lies on the top of it like an Island Tills with olhor similar occurrences oc-currences has led me to think that the limestone IH a mailer of no consequence conse-quence in explaining the mineralization of the region though as will be seen hereafter It seems to bu connected with the mineral In one place or more I About six miles up the creek from Cuprum begins the great ore zone of the Seven Devils There the great granite contact comes In nnd runs very nearly north and south on the true strike and Is traceable for at least two I miles In an air line and some four miles or more by trail The vein dips at crying angles but will average nearly h 0 degrees from vertical to the cast this with thc great slope of the mountains moun-tains from the While Monument Halm southward seems to throw thu vein far to the southeast In an arc of a circle as It passes through the Alaska and Blue Jacket to the Decorah At the latter group the vein seems tp be lost but 11 or a similar group of veins conies to the surface a short distance south In what Is called the Bear Basin Here however the veins seem to carry car-ry gold and little or no copper whllo northward they are distinctly copper veins carrying little else hut Iron and garnet From the Decorah to IIU AVhlte Monument the chief vein appears ap-pears to be on the contact of the granite gran-ite and lime or marble as It should be called but there are several other veins which seem to run parallel with this main vein which lie wholly In the granite and lo the eastward of It this vein Beyond the While Monument the granite conlact swings to the northwest and seems to carry some veins with it but tho largest veins keep on their course leaving the contact con-tact and culling through the granite as far as Helena which lies to the north of the main ridge but still on the Snake river side o At Helena the greatest outcrop of the region Is found and wholly In granite I is several hundred feet wide and has radiating from it like tho spokes of n wheel a number of veins with simi lar filling some of them twenty feet wide In places Tills is In addition to the olher parallel veins which lie lo the east ofit as has been mentioned before North of Helena there Is not so distinct a situation us to enable a I person to state with certainty what becomes of the great veins though there are plenty of theories All the veins in this region are uniformly filled with garnet gangue and have no well defined porphyry dykes adjoining though theso must occur They arc quite wide for the most part and excessively ex-cessively wide where the chutes arc found In the Blue Jacket the main vein Is eighty feet wide and In or near the Peacock there Is a place where it s mst be at least 100 feet wide There are several places where It is thirty or more feet wide This garnet is somewhat spotted with copper but w1 average from 3 to 5 per cent copper cop-per thrpughout and has about 3000000 tons of this kind of copper In sight On the foolwall of the main vein the copper is condensed In chutes varying from a few Inches lo ten feet or more of bornle which will run throughout about 35 per cent copper This Is above the waler level J3How this the copper seems lo be u straight copper pyrite So far about live of these chutes have been found between the Peacock and the Decorah A peculiar fealure of these ores Is that they carry no arsenic ar-senic unlirnony or zinc The development develop-ment In thtls region Is slight considerIng consider-ing the time the claims have been known There Is hardly IL mine In the camp that Is down more than 100 feet and yet the Blue Jacket his been shipping ship-ping 10 per cent copper ore for nearly a year When the railroad reaches this regIon it is I probable that all oro over 15 per cent copper will be shipped In the Blue Jacket Ihc copper chute lies on the lime and presimts the usual Irregular Ir-regular shape which lime deposits show When we take Into con ldera lion the width of the veins and the continuous outcropping for over Iwo miles in an air line we can get some Idea of the Iiuiiitiisc quantity of copper which lies In this region to say nothing I of the many smaller veins which us yet have not been opened a n Rapid river heads about three miles In an air line from Helena nnd to the northeast At Its head there Ire several sev-eral veins opened but whoso mineral izallon 1 am not familiar with though the veins seum lo run in the se01 111 II thl sam general gen-eral direction as those of Cuprum and Helena About twelve miles down Ihla I river there Is an Immense outcropping of veins which ul first sight seem to I put all others In tho shade These have all the elements which please n geologist except the filling Thero wo have the great porphyry dykes several sev-eral hundred feet wide running as true as 0 die and having on the con tacl immense veins of quartz with copper cop-per shot all through them but unfortunately unfor-tunately not enough lo pas to work Some of the owners of these veins wIth commendable pluck have put money into them to see If they do not go down since all of them carry some gold as well au copper I Is to be hoped that they may Jiuccced I At Carvers on the Salmon river and on the north end of the Seven Dovlls I there Is 0 very promising series of gold veins MARCUS R JONES Nevadas Klondike Messrs Bell and Courl have received their returns from ore shipped to Sel byB smelling works The ore worked 300 ounces in silver 313 In gold and 25 per cent In lead Tho returns gave I penernl cptlpfuctlon t Slnr < this bve was extracted they have sunk an incline in-cline thirty Ted in depth The ole has Increased 1 gold every foot At lie bottom of the Incline It averages 131 in gold M S Sharp of Morey has discovered dis-covered amino called the Silver Knight he has tapped Hit ledge about eighteen feet in depth the width of the ledge Is four feet Mr JL Couit look Ihree samples from the Icdgx The llrst assayed MK > ounces the second 1000 ounces the third lliOO ounces in silver Klondike promises to be one of the largest silver and gold producing produc-ing camps In the State There Is no doubt that when depth Is attained all the mines will produce J highgrade carbonate car-bonate ores Hchnont Nov Courier |