Bu,«»N..M ^ESS&KSP'* DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY CHARLES D. WALCOTT, DIRECTOR CONTRIBUTIONS TO MINERALOGY FROM THE UNITED STATES GEOLOGICAL SURVEY BY F. W. CLARKE, W. F. HILLEBRAND, F. L. RANSOME, S. L. PENFIELD, WALDEMAR LIND6REN, GEORGE STEIGER, AND W. T. SCHALLER WASHINGTON GOVERNMENT PRINTING OFFICE 1905 ' CONTENTS. Tago. Letter of transmittal, by G. F. Becker ..................................... ' 5 Prefatory note, by F. W. Clarke........................................... 7 On carnotite and associated vanadiferous minerals in western Colorado, by W. F. Hillebrand and F. Leslie Bansome ................................ 9 Some additions to the alunite-jarosite group of minerals, by W. F. Hillebrand and S. L. Penfield.................................................L.... 32 Minerals from the Clifton-Morenci district, Arizona, by Waldemar Lindgren and W. F. Hillebrand.................................................. 42 Two tellurium minerals from Colorado, by W. F. Hillebrand.....i.......... 55 Notes on lawsonite, by W. T. Schaller and W. F. Hillebrand................ 58 The composition of yttrialite, with a criticism of the formula assigned to thal&iite, by W. F. Hillebrand.......................................... 61 A pseudo-serpentine from Stevens County, Wash., by F. W. Clarke.......... 69 On " californite," by F. W. Clarke and George Steiger...................... 72 The action of silver nitrate and thallona nitrate upon certain natural silicates, by George Steiger ........................................................ 75 Dumortierite, by W. T. Schaller........................................... 91 Mineralogical notes, by W. T. Schaller..................................... 121 Index .........-...--.._-.-..-...---- --...---.---..-----------.--..---. 145 3 ILLUSTRATIONS. FIG. 1. Natrojarosite .................^...i...........................j... 32 2. Plumbojarosite ................................................... 35 3. Dioptase ..............!:.......................................:. 46 4. Libethenite.......................'................................ 51 5. Lawsonite........................................................ 59 6. Dumortierite altering to muscovite ................................. 101 7. Forms of dumortierite............................................. 104 8. Dumortierite ...................................................... Ill 9. Tellurite ......................................................... 127 10. Anhydrite. ......................................................... 132 11. Glaucodot............................-.-.---.-......---.-..-.---. 133 12. Libethenite-......-...-.---......--.-.-...-..-....----..---.--..-- 141 LETTER OF TBANSMITTAL. DEPARTMENT OP THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, ' Washington,]). C., January 31, 1905. SIR: I have the honor to transmit herewith a series of papers by various hands for publication as a bulletin. They represent mineral- ogical investigations incidental to geological researches arid important to the progress of geology, and are here brought together for con­ venience of reference. Very respectfully, G. F. BECKER, Geologist in Charge Division of Chemical and Physical Research. Hon. CHARLES D. WALCOTT, Director United States Geological Survey. CONTRIBUTIONS TO MINERALOGY FROM THE UNITED STATES GEOLOGICAL SURVEY. PREFATORY NOTE. By F. W. CLAKKE. Although mineralogical research occupies a relatively small place among the many varied activities of the United States Geological Survey, it is by no means neglected. From time to time interesting material is collected by the field parties of the organization, and speci­ mens deserving study are received from other sources. These are worked up, as opportunity offers, in the chemical laboratory of the Survey, sometimes independently and sometimes, as in the work reported in two of the memoirs here presented, in cooperation with the geologists by whom they were brought in. Occasionally assistance is received from investigators not connected with the Survey, and one such case is now represented by the joint paper of Doctor Hillebrand and Professor Penfield. of Yale University. In that instance the chemical work was done in Washington and the cry stall ographic measurements were made at New Haven. Most of the papers contained in this bulletin represent investigations which are complete within themselves. The work done by Mr. Steiger upon the silver and thallium derivatives of the zeolites, how­ ever, is to be regarded as one part of a series of researches upon the constitution of the silicates. Some parts of this series have been already published, and it is hoped that this work may be continued in the future. The field to be covered is enormous and progress within it is necessarily slow. Still, the results obtained so far are definite and significant, especially as they show a chemical plasticity among the silicates which was formerly unsuspected. Some of the items of more than ordinary interest to be found within these pages are as follows: Three new mineral species moren- cite, coronadite, and plumbojarosite are described. Natrojarosite, 8 CONTRIBUTIONS TO MINERALOGY. [BULL.202. although, not* absolutely new, is now thoroughly established as a definite mineral. The true character of carnotite is shown in Doctor Hillebrand's research, and the same chemist has worked out more fully than his predecessors the composition of yttrialite and its rela­ tions to other species. Mr. Schaller's very complete study of dumortierite is also worthy of especial mention, and his notes upon other minerals from California are but the first fruits of .a much larger research which is already well under way. ON CARNOTITE AND ASSOCIATED VANADIFEROUS MINERALS IN WESTERN COLORADO. By W. F. HILLEBRAND and F. L. RAN SOME. INTRODUCTION. By W. F. HlLLEBRAND. The rather widespread occurrence in western Colorado of consider­ able quantities of a canary-yellow ore of uranium has been known for a few years past. It has been marketed to the extent of a few tons, but its mineralogical nature was unknown or incorrectly surmised until 1899. In the spring of that year a specimen of this ore first reached my hands through Dr. George P. Merrill, of the United States National Museum, and v.as soon found to contain a mineral or minerals new to science. Within a week appeared the announcement by MM. C. Friedel and E. Cumenge" of a new mineral, carnotite, a hydrous vanadate of uranium and potassium, obtained through Mr. Poulot of Denver, from Roc Creek, Montrose County, Colo. Mr. Poulot had already identi­ fied vanadium in it. It was at once seen, despite certain differences in composition, that the two were identical. According to the French authors the mineral is of simple composi­ tion, as above expressed, with only a little iron and mere traces of Al, Ba, Cu, Pb, and also, according to M. and Mme. Curie, of the radio-active substances radium and polonium. The empirical formula 2UaO3, V2Or>, K2O, 3Hj,O, was^ssigned to it, some doubt attaching to the Avater. - Since then I have been able to examine carnotite from several local­ ities in western Colorado, finjding in each case the same lack of agree­ ment with the analyses of Friedel and Cumenge. While I was engaged in this work my attention was called to certain more or less greenish sandstones from the vicinity of Placerville on the San Miguel River, San Miguel County, Colo., which were said to be highly vanadiferous and of considerable extent, and in which a zone (iBull. Soc. Chim. de Paris (3), xxi, 328,1899; Bull. Soc. Franc. Min., xxii, 26,1899; Comptes Rendus, cxxviii, 632,1899; Chemical News, Ixxx, 1C, 1899. The papers as published in French differ slightly. 10 CONTRIBUTIONS TO MINEKALOGY. [BULL. 202! a few inches thick was rather strongly impregnated with a yellow mineral resembling and probably identical with carnotite. This min­ eral appeared also scattered through the sandstone at other points in sporadic small patches, sometimes visible only by aid of a lens. This occurrence led to the thought that the carnotite bodies farther west might also be associated with existing or dependent on preexist- ent vanadif erous sandstones. For the carnotite of Montrose and Mesa counties, as is stated by the French authors, occurs mixed in all pro­ portions with quartz-sand grains, the remnants, beyond doubt, of former sandstone bodies, and it was soon recognized that in the car­ notite bodies the vanadium existed in two conditions, the larger part b}r far as pentavalent vanadium in the easily soluble carnotite, and a smaller and sometimes hardly distinguishable portion as trivalent vana­ dium in a much less soluble silicate which was free from uranium. It was hoped that, by a field reconnaissance, observations bearing on these points would be obtained and material assembled which would on analysis help to determine the nature and explain the association of these two entirely different classes of mineral substances. The field and microscopical observations of Messrs. Ransome and Spencer are embodied in the pages immediately following these intro- ductoiy remarks. Unfortunately their collections, except those from Placerville, came to hand so late that the chemical work on the more western occurrences has been confined to the carnotite bodies alone, specimens of which were already in my hands. Greenish sandstones have been observed by Messrs. Ransome and Spencer in those regions, but whether any of them are highly Vanadif erous, or what their con­ nection