Dielectric Constants of Diaspore and B-, Be-, and P-Containing Minerals, the Polarizabilities of B2o3and P2os,And the Oxide Additivity Rule
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Key to Rocks & Minerals Collections
STATE OF MICHIGAN MINERALS DEPARTMENT OF NATURAL RESOURCES GEOLOGICAL SURVEY DIVISION A mineral is a rock substance occurring in nature that has a definite chemical composition, crystal form, and KEY TO ROCKS & MINERALS COLLECTIONS other distinct physical properties. A few of the minerals, such as gold and silver, occur as "free" elements, but by most minerals are chemical combinations of two or Harry O. Sorensen several elements just as plants and animals are Reprinted 1968 chemical combinations. Nearly all of the 90 or more Lansing, Michigan known elements are found in the earth's crust, but only 8 are present in proportions greater than one percent. In order of abundance the 8 most important elements Contents are: INTRODUCTION............................................................... 1 Percent composition Element Symbol MINERALS........................................................................ 1 of the earth’s crust ROCKS ............................................................................. 1 Oxygen O 46.46 IGNEOUS ROCKS ........................................................ 2 Silicon Si 27.61 SEDIMENTARY ROCKS............................................... 2 Aluminum Al 8.07 METAMORPHIC ROCKS.............................................. 2 Iron Fe 5.06 IDENTIFICATION ............................................................. 2 Calcium Ca 3.64 COLOR AND STREAK.................................................. 2 Sodium Na 2.75 LUSTER......................................................................... 2 Potassium -
The Thermal Transformation of Datolite, Cabsio4(OH), to Boron.Melilite
MINERALOGICAL MAGAZINE, JUNE I973, VOL. 39, PP. 158-75 The thermal transformation of datolite, CaBSiO4(OH), to boron.melilite J. TARNEY, A. W. NICOL, and GISELLE F. MARRINER Departments of Geology, Minerals Engineering, and Physics, respectively, University of Birmingham SUMMARY. A kinetic and X-ray study of the dehydroxylation of datolite, CaBSiO4(OH), has shown that the decomposition occurs very rapidly above 7o0 ~ in air, with an activation energy for the reaction of the order of 200 kcal mole-1. The transformation is topotactic, the dehydroxylated phase being tetragonal with a 7" 14/~t, c 4-82 fit, and particularly well formed even at the lowest temperatures of decomposition. Single-crystal studies have shown that two orientations of the new phase exist and that the original a of datolite becomes the unique axis of the tetragonal phase while the tetragonal a axes are oriented either parallel to or at 45 ~ to the b and c axes of datolite. The new phase appears to be a boron-containing analogue of the melilite structure, composition Ca2SiB~OT, but is metastable. The basic sheet structure is preserved during the transformation but a reorganization of the tetra- hedral layer from the 4- and 8-membered rings of datolite to the 5-membered rings of the new phase is involved, together with effective removal of protons and some silicon. The transformation can be explained in terms of an inhomogeneous reaction mechanism involving migration of calcium and boron into the new phase domains and counter-migration of silicon and protons, but with only minor readjustment of oxygens. -
Examples from NYF Pegmatites of the Třebíč Pluton, Czech Republic
Journal of Geosciences, 65 (2020), 153–172 DOI: 10.3190/jgeosci.307 Original paper Beryllium minerals as monitors of geochemical evolution from magmatic to hydrothermal stage; examples from NYF pegmatites of the Třebíč Pluton, Czech Republic Adam ZACHAŘ*, Milan NOVÁK, Radek ŠKODA Department of Geological Sciences, Faculty of Sciences, Masaryk University, Kotlářská 2, Brno 611 37, Czech Republic; [email protected] * Corresponding author Mineral assemblages of primary and secondary Be-minerals were examined in intraplutonic euxenite-type NYF peg- matites of the Třebíč Pluton, Moldanubian Zone occurring between Třebíč and Vladislav south of the Třebíč fault. Primary magmatic Be-minerals crystallized mainly in massive pegmatite (paragenetic type I) including common beryl I, helvite-danalite I, and a rare phenakite I. Rare primary hydrothermal beryl II and phenakite II occur in miarolitic pockets (paragenetic type II). Secondary hydrothermal Be-minerals replaced primary precursors or filled fractures and secondary cavities, or they are associated with ,,adularia” and quartz (paragenetic type III). They include minerals of bohseite-ba- venite series, less abundant beryl III, bazzite III, helvite-danalite III, milarite-agakhanovite-(Y) III, phenakite III, and datolite-hingganite-(Y) III. Chemical composition of the individual minerals is characterized by elevated contents of Na, Cs, Mg, Fe, Sc in beryl I and II; Na, Ca, Mg, Fe, Al in bazzite III; REE in milarite-agakhanovite-(Y) III; variations in Fe/Mn in helvite-danalite and high variation of Al in bohseite-bavenite series. Replacement reactions of primary Be- -minerals are commonly complex and the sequence of crystallization of secondary Be-minerals is not defined; minerals of bohseite-bavenite series are mostly the latest. -
Crystal Structure of Protoamphibole
Mineral. Soc. Amer. Spec. Pap. 2, 101-109 (1969). CRYSTAL STRUCTURE OF PROTOAMPHIBOLE G. V. GIBBS Department of Geological Sciences, Virginia Polytechnic Institute Blacksburg, Virginia 24061 ABSTRACT The structure proposed for protoamphibole (Gibbs et al., 1960) has been verified and refined by three-dimensional Fourier and least-squares methods using data collected with a Weissenberg single crystal counter-diffractometer. The symmetry is Pnmn with a = 9.330, b = 17.879 and c = 5.288 A and the unit-cell content is 2(Nao.03Li",oMg, ••) (Si r. ,.Alo.040,1.71) (OHo.15F,.14). The structure consists of layers of interlocking chains of fluorine-centered hexagonal rings of SiO. groups. The layers are bound together by Mg.Li cations which are coordinated between the chains, the coordination being effected by a ~(cI3) stagger between adjacent layers. An additional stagger of ~(-cI3) in the sequence along a gives an overall displacement of zero between alternate layers, accounting for the 9.33 A a cell edge and the orthogonal geometry. The direction of stagger can be related to the placement of the cations in the octahedral layer. The M -cation coordination groups are nearly regular octahedra with the exception of M(4) which is similar to Mg(l) in protoenstatite. The M(3), M(1) and M(2) sites are occupied principally by Mg. In addition to being randomly distributed around the cavity walls of the A-site, Li ions are also segregated in about 25% of the M(4) sites, the others being occupied by Mg ions. The individual Si-O bond distances in the chains are consistent with Cruickshank's d-p -n: bonding model: Si-O(non- bridging) bonds [Si(1)-O(1) = 1.592; Si(2)-0(4) = 1.592; Si(2)-0(2) = 1.605 AJ are significantly shorter, on the average, than the Si-O(bridging) bonds [Si(1)-0(5) = 1.616; Si(1)-0(6) = 1.623; Si(1)-0(7) = 1.624; Si(2)-0(5) = 1.626; Si(2)-0(6) = 1.655 AJ. -
Gem Crystal Surface Features Spherical Cultured Pearls Aquamarine
Gems&Jeweller y Spring 2012 / Volume 21 / No. 1 Gem crystal Spherical Aquamarine- surface features cultured pearls coloured glass The Gemmological Association of Great Britain MARCUS MCCALLUM FGA PRECIOUS STONES, BEADS & PEARLS A wide range of precious and semi-precious stones, beads and freshwater pearls, personally selected from around the world. Unusual stones a speciality. ROOM 27-31, NEW HOUSE 67-68 HATTON GARDEN, LONDON EC1N 8JY TELEPHONE: +44(0)20 7405 2169 FACSIMILE: +44(0)20 7405 9385 email:[email protected] www.marcusmccallum.com Gems&Jewellery / Spring 2012 / Volume 21 / No. 1 Gem-A CalendarEditorial Gems&Jewellery Winds of change This year is turning in to a busy one for Gem-A. As reported in Gem-A News and Views (page Spring 40), we have a lease renewal on our Greville Street premises which will lead to a thorough refurbishment — something which those of you who know the building will agree is much needed. This will provide an excellent opportunity to reinvigorate both our onsite teaching facilities and the services we can offer members. How can we afford this you may ask, when only a very few years 12 ago the Association was in poor health financially? The fact is that over the last few years we have run a very tight ship knowing we had these costs looming. We have focused on what we are good Contents at and the things which are the core aspects of our business. This has led to the ceasing of loss- making operations, such as the laboratory, and an increase in students and thus revenue from our education, though it must be qualified that this increase is from overseas rather than the UK. -
NVMC Nov 2019 Newsletter.Pdf
The Mineral Newsletter Meeting: November 18 Time: 7:45 p.m. Long Branch Nature Center, 625 S. Carlin Springs Rd., Arlington, VA 22204 Volume 60, No. 9 November 2019 Explore our website! November Meeting Program: Making Sugarloaf Mountain (details on page 5) In this issue … Mineral of the month: Datolite ................. p. 2 November program details ........................ p. 5 Annual Holiday Party coming up! ............. p. 5 President’s collected thoughts .................. p. 5 October meeting minutes .......................... p. 7 Nominations for 2019 club officers ........... p. 8 Datolite nodule Club show volunteers needed! .................. p. 8 Quincy Mine, Michigan Bench tip: Sheet wax with adhesives ......... p. 9 Source: Brandes (2019). Photo: Paul T. Brandes. Annual show coming up—Help needed! .. p. 10 EFMLS: Wildacres—finally! ........................ p. 12 AFMS: Scam targets mineral clubs ............ p. 13 Safety: Be prepared ................................... p. 13 Deadline for Submissions Field trip opportunity ................................. p. 14 November 20 Manassas quarry geology, pt. 2 ................. p. 15 Please make your submission by the 20th of the month! Upcoming events ....................................... p. 20 Submissions received later might go into a later newsletter. 28th Annual Show flyer ............................. p. 21 Mineral of the Month Datolite by Sue Marcus Datolite, our mineral this month, is not a zeolite, alt- hough it often occurs with minerals of the Zeolite Group. It can form lustrous crystals or attractive masses that take a nice polish. And, for collectors like Northern Virginia Mineral Club me, it is attainable! members, Etymology Please join our guest speaker, Joe Marx, for dinner at Datolite was named in 1806 by Jens Esmark, a Danish- the Olive Garden on November 18 at 6 p.m. -
Two Yttrium Minerais
TWO YTTRIUMMINERAIS: SPENCITE AND ROWLANDITE1 CLIFFORDFRONDEL Haruar d, Univ ersity, Cambr,i.d,ge,M assachusetts Assrnecr Spencite is a new borate-silicate of calcium and yttrium, (Ca, Fe)2(Y,La)a(BaSin.aAl.z)s(O, OH, F, Cl)20 fro11 1 pegmatite in Cardiff township, Haliburton County, Ontario. Found as dark reddish brown to brownish black anhedral masses.Hardneis B$, specific gravity 8,08. Metamict; isotropic with n near 1.630. when the mineral is heated at 925" i the n increases to about 1.640 and the specific gravity to 8.20. At high temperatures the mineral decomposesbefore it recrystallizes and r-ray difiraction daticannol be obtained. spencite is related chemically to the minerals of the Datolite Group and may be iso- structural with them. It is named after the canadian mineralogist Hugh s. Spence. A re-examination of the little known mineral rowlandite from Baringer Hiil, Texas, establishesit as a valid species.Composition near (y, Fe, Ce)s(SiOa)r(F,0H). Metamict; with n 1.704. Hardness 5$, specific gravity 4.Bg; *-ray powder data are given foi material recrystallized in nitrogen at 900" c (with tnean n 1.76, specific gravity a.65). Spsxcne This new mineral was collected by Hugh S. Spence in 1gB4 from a prospect pit in Cardiff township, lot 7, concessionXX, Haliburton County, Ontario, and was tentatively identified as thalenite. It occurred as massesin a narrow pegmatite stringer in a vuggy pyroxenite, associated with calcite, red apatite crystals, diopside, purple fluorite, and wernerite, about 200 feet from an outcrop of normal reddish granite pegmatite. -
Siu\,I-Bearing Alteration Product of Pectolite M
44 THE AMERICAN MINENAI,OGIST A NEW OCCURRENCE OF STEVENSITE, A MAGNE- SIU\,I-BEARING ALTERATION PRODUCT OF PECTOLITE M. L. CLENN Erie, Pennsglaonia IN rnn old Hartshorn qua,rry, in Springfield Township, Essex County, New Jersey, Mr. Louis Reamer of Short Hills, N. J., discovered a single vein of a peculiar mineral, called by the quarrymen "magnesium" (:talc?) and submitted samples of it to the writer for identification. It proved to be essentially identical with the hitherto imperfectly known steuensite,the nature of which is discussed in this article. The quarry lies some 16 miles southwest from the better known mineral localities around Paterson, but is in the same rock, the basalt of First Watchung Mountain. The rock is, if anything, more altered than that at Paterson, and the mineralogical association is some- what different from that at the latter place. The most unusual feature is the abundance of a secondary feldspar, in aggregates of sheaflike and " cocks-cotlb " crystals, whieh shows the op- tical properties of anorthoclase.I There are also t.rumeroussmall quartz crystals, usually iron-stained; drusy prehnite in small pockets; many calcite crystals; a little pectolite and datolite; and several zeolites. Of the Iatter natrolite, stilbite and heu- landite were the only ones noted by the writer, no trace of apo- phyllite, chabazite, or laumontite, so common at other similar localities, being observed. Some of the pectolite found at the quarry is of the usual type, silky radiations of fine needles, but the greater part of it shows marked evidenee of alteration, the color becoming more and more pinkish and the luster more and more waxy toward the outer ends of the radiations. -
Datolite, Schorl) and Alumosilicates (Andalusite, Sillimanite) in the Oketo Rhyolite, Hokkaido
Title Borosilicates (Datolite, Schorl) and Alumosilicates (Andalusite, Sillimanite) in the Oketo Rhyolite, Hokkaido Author(s) Watanabe, Jun; Hasegawa, Kiyoshi Citation 北海道大学理学部紀要, 21(4), 583-598 Issue Date 1986-02 Doc URL http://hdl.handle.net/2115/36742 Type bulletin (article) File Information 21_4_p583-598.pdf Instructions for use Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP Jour. Fac. Sci., Hokkaido Univ., Ser. IV, vo l. 21, no. 4, Feb., 1986, pp. 583-598. BOROSILICATES (DATOLITE, SCHORL) AND ALUMOSILICATES (ANDALUSITE, SILLIMANITE) IN THE OKETO RHYOLITE, HOKKAIDO by Jun Watanabe and Kiyoshi Hasegawa* (with 1 text-figure, 4 tables and 6 plates) Abstract The second occurrence of dalOlite in Hok kaido, after the first report from the Furano mine (Sako et a I. , 1957; Saw el aI., 1967), is herein described from the Oketo Rhyolite (Watanabe et aI., 1981a, 1981b), Kitami Province, Hokkaido. Datolite fr om the Oketo Rhyolite occurs in the small veinlets cutting the metasomatic facies of the rhyolite of the Miocene in trusion. Optical data of the datolite are: a= 1.625, (j; 1.652, ")'= 1. 669. 2Vx = 71. 0-72.0° . Lallice constalll s are: a = 9.62 A, b = 7.60 A, c = 4.83 A, ci a = 0.50, {j = 90° II ' . X-ray data is shown in Table I. Chemical data are: C3.4.o2B4. IISiJ.90015.96( OHkO-l to C34.23B3.68SW.IIOIS.93(O H)4.07 on the basis o f 20 (0, O H), namely as the empirical formula is given CaU)o.. 1.06 BI.OJ.O.92S iO.97. -
FLUORINE in HAMBERGITE] Groncb Swrtzrt, Rov S. Clenxo, Jn., T/. S. L
THE AMERICAN MINERALOGIST, VOL. .50, JANUARY-FEBRUARY, 1965 FLUORINE IN HAMBERGITE] GroncB Swrtzrt, Rov S. Clenxo, Jn., t/. S. l{otional Museum, W ashington,D. C.; Jonu SrNxeNxes, Scripps Institute of Oceanography,Lin'iz:ersity oJ CaliJornio, La Jolla; aNt HBT.BNW. WonrurNc, [/. S' Geologi,cal S wrttey, Il/ ashi,ngton,D. C. Aesrnecr A chemical analysis of hambergite [Be:(OH, F)(BOt] from the Little Three mine, near Ramona, San Diego County, California, disciosed that the minerai from this Iocality contains 6.0 per cent fluorine. Hambergite from a secondCalifornia localitl., the Himalaya mine near Mesa Grande, contains 0.2 per cent fluorine Fluorine $'as not reported in analyses in the ]iterature of hambergite from Madagascar, Norway, and Kashmir' New analyses of Madagascar and Norway hambergite gave 1 0 and 0 15 per cent fluorine, re- spectively. No material from Kashmir u'as available for study. New data on hambergite from Anjanabanoana, Madagascar, and the Little Three mine, California, follow: Madagascar-BeO 53.6, 8z0136.0,HrO 8.8, F 1.0, iessO-F 0.4, sum 99.0 per cent; orthorhombic,a:9.76+O.Ol, b:12.23+O-01' c:4.43*0.01 A. Cali- fornia-BeO 529,82Ot36.6, HrO 6.7,F 6 0, O=F 2.5, sum 99'4per centlorthorhombic, a:9 78+0.01,b:12.40+0.01 , c:447+0.014; density2.372 (obs) gms/cm3;a:1.543, B:1.580, "r:1 617+0.001,2Y:90o. Crystals from the Little Three mine shou'two new forms, 13401and {341}. -
Mineralogy and Geochemical Evolution of the Little Three
American Mineralogist, Volume 71, pages 406427, 1986 Mineralogy and geochemicalevolution of the Little Three pegmatite-aplite layered intrusive, Ramona,California L. A. SrnnN,t G. E. BnowN, Jn., D. K. Brno, R. H. J*rNs2 Department of Geology, Stanford University, Stanford, California 94305 E. E. Foono Branch of Central Mineral Resources,U.S. Geological Survey, Denver, Colorado 80225 J. E. Snrcr,nv ResearchDepartment, Gemological Institute of America, 1660 Stewart Street,Santa Monica, California 90404 L. B. Sp.c,uLDrNG" JR. P.O. Box 807, Ramona,California 92065 AssrRAcr Severallayered pegmatite-aplite intrusives exposedat the Little Three mine, Ramona, California, U.S.A., display closelyassociated fine-grained to giant-texturedmineral assem- blageswhich are believed to have co-evolved from a hydrous aluminosilicate residual melt with an exsolved supercriticalvapor phase.The asymmetrically zoned intrusive known as the Little Three main dike consists of a basal sodic aplite with overlying quartz-albite- perthite pegmatite and quartz-perthite graphic pegmatite. Muscovite, spessartine,and schorl are subordinate but stable phasesdistributed through both the aplitic footwall and peg- matitic hanging wall. Although the bulk composition of the intrusive lies near the haplo- granite minimum, centrally located pockets concentratethe rarer alkalis (Li, Rb, Cs) and metals (Mn, Nb, Ta, Bi, Ti) of the system, and commonly host a giant-textured suite of minerals including quartz, alkali feldspars, muscovite or F-rich lepidolite, moderately F-rich topaz, and Mn-rich elbaite. Less commonly, pockets contain apatite, microlite- uranmicrolite, and stibio-bismuto-columbite-tantalite.Several ofthe largerand more richly mineralized pockets of the intrusive, which yield particularly high concentrationsof F, B, and Li within the pocket-mineral assemblages,display a marked internal mineral segre- gation and major alkali partitioning which is curiously inconsistent with the overall alkali partitioning of the system. -
Download the Scanned
,7 B6 o 6 Fr z* F] EZ Hv a TnB AuBntcAN MtxBnALocIST Vol. 4 SEPTEMBER, 1919 No. 9 BULLETIN OF THE NEW YORK NIINERALOGICALCLUB, 2,2. THE MINERALS OF THE BERGEN ARCHWAYS' JAMES G. MANCHESTER New York CitY Bergen Hill is about 19 kilometers (12 miles) long and 1'6 kilometers (1 mile) wide, comprizing a range of bluffs of Triassic diabase. It commencesat Bergen Point and r',-rnsbehind Jersey City and Hoboken to a point in S-eehawken about opposite Thirty-fifth Street in Nerv York City. Here it comes close to the Hudson River and continues north for some 29 kilometers (18 miles) to Piermont, being known as the Palisades' The Bergen Hill region has long been noted as a locality for zeolites and associated minerals. When the announcement was made that the Erie Railroad Company had begun the construc- tion of an open cut thru the hill, local collectors interested in mineralogy looked forward to the collecting of fine specimens' This interest was fully justified from the history of past borings thru Bergen hill. In the construction of the Pennsylvania cut at Mount Pleasant, the Erie and the two Lackawanna tunnels at operations are shown on the map, Fig. 1, on the succeedingpage' The construction of the new cut was commenced in October, 1906, and with a force of 1,100 men working in day and night shifts, the work was completed in June, 1910, requiring three and two-thirds years to build. The cost of this new entrance to Ner.vYork City amounted to $8,000,000' The task of cutting thru the hill was stupendous' The cut is 1,300 meters long and 80 per cent.