| OCR Text |
Show 66 outlying developed occurrences of vanadium ore (the Mesa Creek group In T. 49 N., R. 17 W., Mesa County, Colorado, the Pitchfork mine in T. 44 N., R. 16 W», San Miguel County, Colorado and the Souaw Canyon mines of T. 38 S., R. 26 E., San Juan County, Utah). Toward the southwestern limit of the subject lands, the southwestern limit of known vanadium m i n e r a l i z a t i o n extends to the southwest beyond the area where subject lands occur in t r a c t s of s u f f i c i e n t i n d i v i dual size or s u b s t a n t i a l concentration to J u s t i f y explorat i o n . For t h i s reason the economic boundary of vanadium mineralization with respect to subject lands was determined where t h i s change in t r a c t size and concentration of subject lands occurs. The'eastern limit of known vanadium mine r a l i z a t i o n and the economic boundary of vanadium mine r a l i z a t i o n were both shown on the series of maps, PV-225, 1-12. Customary engineering methods for the measurement of map areas by use of the planimeter permitted the determination of the known vanadium-bearing subject lands of the Southwestern Colorado area to be 325,690 acres. Field studies of the vanadium-bearing formations and developed mining properties and knowledge of the history of the development of this mineral area Indicate that all of the vanadium-bearing formation is not of uniform value. For this reason the total area of vanadium-bearing lands was classified into five categories representing five different |
