Show manganese in green gr een river region to meet the urgent needs odthe of the united states and the allies for manganese the united states geological survey has sent its geologists into areas where manganese mining is in progress and into other areas that contain rocks for the purpose of estimating the possible production and determining the ore reserves the geological survey has just reported the results of such a reconnaissance made by J T pardee one of its geologists between may and may last of square miles in the green river district south of the denver rio grande railroad between thompson and green river utah the work done included a thorough examination of twenty manganese mines and a detailed survey of four square miles in the vicinity of the C F I 1 mine made in order to fabii facilitate tate a close estimate of the ore reserves the ore the manganese ore occurs as aa irregular lenses or blankets that lie a few feet below 7 the surface along the bedding planes of a calcareous red stand stone near the middle of the mceldo formation jurassic as veins and neumar eions along joints below the blankets and as fragments in the soil residual from the weathering of ore of the two forms first mentioned in the area examined the rocks dip but a few degrees from the horizontal and the surface trace of the ma stratum is therefore a very sinuous line winding around mesas cliffs and canyons from a point near green river the outcrop of the beds runa in general southeastward about twenty five miles and thence apparently swings nort northeastward hea stward around the la sal mountains A bed is reported to crop out at many places from green river westward to and beyond the san rafael swell manganese occurs rather persistently along the part of the bed that was examined but only in places is it pure enough or in bodies large enough to be considered ore few of the blanket deposits are more than fifty feet long and most of anem measure twenty feet or less generally they are closely spaced for a mile or f wo rich or workable areas that are separated by long barren stretches ordinarily the workable blankets range rang e in thickness from two to six inches but a few reach a thickness of three feet loose fragments of ore are arc scat terea over thousands of acres but owing to variations in their distribution ana in tile the proportion of fragments of rock mixed them only comparatively small arena atre woric able under present conditioner condition rp in places the fragments of ora ore most of them about completely cover the as big as a walnut ground and can be easily raked up and loaded in wagons ordinarily however in the workable areas the fragments are distributed through a foot or less or sandy b soil the completely disintegrated matrix of the original ore bodies this dry screening ground will yield ten to or more of ore a square yard but generally not more than twenty five pounds the bulk of the ore has thu properties or which as suggested by commonly occurring crystal forms is probably secondary or after manga pite wad is widespread but not abundant and ch rosite occurs sparingly in two iwu mines minea high grade many of the blanket deposits appear to be almost pure manganese dioxide several carloads have been shipped that carried 70 to 85 per cent of manganese flox dioxide ae tre principal impurities being lime ihme silica the oie ore generally contains less than per cent of iron very little phosphorus and rather curiously from a trace to one half of I 1 per cent or more of copper in places the blankets grade into material consisting largely of lime and gypsum the nodular concretions and irregular replacements along joints contain more silica than the ore of the blankets the residual ore in the soil generally contains 40 per cent or more inore of manganese from 8 to 15 pe ent of silica and less than 2 per cent of iron an air average of thirty five car samples of mixed ore shipped from the C F I 1 mine contained 4 13 per cent of manganese per cent ot of silica and 15 per cent of iron it is interesting to record the fact that strontium sulphate occurs in beds from one to six inches thick associated with gypsum in the gani ferous stratum at several places in the C F 1 I mine according to mr pardee the manganese lime and gypsum were originally deposited in a body of water during the jurassic period and after the region had been uplifted and the stratum un uncovered coverett by erosion in late tertiary time the ore bodies that are now exploiter exploit ea were formed by the action of surface waters it is not clear whether concentration of the manga nese is still in progress mining most of the m mines ines in this district were operated part of the time during 1916 and 1917 at present three operators are producing to tons of high grade manganese ore a in month anth most of this ore comes from the C F 1 I and salt wasn gasn mines minei operated by the green river mining com pany the other active operators are the needles mining company and J B s fonder the deposits are worked solely by open pits the bedded deposits blankets bear an overburden ranging in iness from a few inches to six feet which is stripped tripped 5 off by hand or with plow and scraper it is rarely profitable to mine them by drifting under cover or to remove more than six feet of overburden residual fragments of manganese ore are separated from the soil by dry screening and hand picking at the C F I 1 mine a revolving screen driven by a gasoline engine has been discarded for one man handshaking hand shaking screens and stationary sloping screens such as are commonly used by mortar mixers to clean sand in this way one man inan can produce from 1000 to 2000 pounds of ore A cay aay T alie lle quantity of ore produced from the blankets by one man is variable but averages nearly the same as that obtained from the residual deposits miners wages are and 4 and board is a day the cost of hauling ore to the railroad from the C F I 1 mine is 4 a ton and the cost at the other mines ranges from 4 to 9 a ton loading hauling water and other expenses br brang ng me cost of a ton of ore on board the cars up to a price ranging from 17 to 25 the operators report difficulty in obtaining suffield sufficient ent labor to run the minea at full capacity it is estimated that a monthly output of at least tons can be maintained at present without modifying existing methods of mining or adding greatly to the equipment on hand if a number of miners can be had ore reserves on may 20 1918 there were tons of ore on the loading platforms at crescent and floy awaiting shipment approximately half of this was selected ore carrying about 80 per cent of manganese dioxide a grade known as dioxide ore by the operators the remainder carries more than 40 per cent manganese and is classified by the operators as furnace or metallic ore mr pardee estimates that tons or high grade ore containing more than 40 per cent of manganese is available for mining under present conditions and without modification of existing methods most of this may be classified as furnace ore though a considerable part of it could be hand sorted to dioxide ore about two thirds of the quantity estimated is contained in the blankets and the remainder in the residual deposits the above estimates include twenty mines two of which supply more than half the total in addition tons chiefly in the r residual e S dual surface deposits are possibly available to mining under improved improve ed conditions or methods I 1 some way other than hand picking should be devised to separate the rock fragments from the ore under present conditions the ore in the green river district that contains much less than 40 per der cent of manganese can not perhaps be mined profitably but sucu ore happens to be not very abundant about tons of ore containing from 15 to 40 per cent of manganese and considerable lime is available for mining in addition there is a considerable amount of ore containing smaller percentages of manganese and much silica most of it in some abandoned claims at the locality known as court house iron ore was observed at only one place where an outcrop promises to yield several hundred tons of apparently low grade material the iron oxides are generally distinct from the manganese and occur chiefly in the layer ne next at below it but no material rich enough to be was sinei as iron ore was seen |