The Wittelsbach-Graff and Hope Diamonds: Not Cut from the Same Rough
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Redalyc.Mineralogical Study of the La Hueca Cretaceous Iron-Manganese
Revista Mexicana de Ciencias Geológicas ISSN: 1026-8774 [email protected] Universidad Nacional Autónoma de México México Corona Esquivel, Rodolfo; Ortega Gutiérrez, Fernando; Reyes Salas, Margarita; Lozano Santacruz, Rufino; Miranda Gasca, Miguel Angel Mineralogical study of the La Hueca Cretaceous Iron-Manganese deposit, Michoacán, south-western Mexico Revista Mexicana de Ciencias Geológicas, vol. 17, núm. 2, 2000, pp. 142-151 Universidad Nacional Autónoma de México Querétaro, México Available in: http://www.redalyc.org/articulo.oa?id=57217206 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Revista Mexicana de Ciencias Geológicas, volumen 17, número 2, 143 2000, p. 143- 153 Universidad Nacional Autónoma de México, Instituto de Geología, México, D.F MINERALOGICAL STUDY OF THE LA HUECA CRETACEOUS IRON- MANGANESE DEPOSIT, MICHOACÁN, SOUTHWESTERN MEXICO Rodolfo Corona-Esquivel1, Fernando Ortega-Gutiérrez1, Margarita Reyes-Salas1, Rufino Lozano-Santacruz1, and Miguel Angel Miranda-Gasca2 ABSTRACT In this work we describe for the first time the mineralogy and very briefly the possible origin of a banded Fe-Mn deposit associated with a Cretaceous volcanosedimentary sequence of the southern Guerrero terrane, near the sulfide massive volcanogenic deposit of La Minita. The deposit is confined within a felsic tuff unit; about 10 meters thick where sampled for chemical analysis. Using XRF, EDS and XRD techniques, we found besides todorokite, cryptomelane, quartz, romanechite (psilomelane), birnessite, illite-muscovite, cristobalite, chlorite, barite, halloysite, woodruffite, nacrite or kaolinite, and possibly hollandite-ferrian, as well as an amorphous material and two unknown manganese phases. -
Metamorphism of Sedimentary Manganese Deposits
Acta Mineralogica-Petrographica, Szeged, XX/2, 325—336, 1972. METAMORPHISM OF SEDIMENTARY MANGANESE DEPOSITS SUPRIYA ROY ABSTRACT: Metamorphosed sedimentary deposits of manganese occur extensively in India, Brazil, U. S. A., Australia, New Zealand, U. S. S. R., West and South West Africa, Madagascar and Japan. Different mineral-assemblages have been recorded from these deposits which may be classi- fied into oxide, carbonate, silicate and silicate-carbonate formations. The oxide formations are represented by lower oxides (braunite, bixbyite, hollandite, hausmannite, jacobsite, vredenburgite •etc.), the carbonate formations by rhodochrosite, kutnahorite, manganoan calcite etc., the silicate formations by spessartite, rhodonite, manganiferous amphiboles and pyroxenes, manganophyllite, piedmontite etc. and the silicate-carbonate formations by rhodochrosite, rhodonite, tephroite, spessartite etc. Pétrographie and phase-equilibia data indicate that the original bulk composition in the sediments, the reactions during metamorphism (contact and regional and the variations and effect of 02, C02, etc. with rise of temperature, control the mineralogy of the metamorphosed manga- nese formations. The general trend of formation and transformation of mineral phases in oxide, carbonate, silicate and silicate-carbonate formations during regional and contact metamorphism has, thus, been established. Sedimentary manganese formations, later modified by regional or contact metamorphism, have been reported from different parts of the world. The most important among such deposits occur in India, Brazil, U.S.A., U.S.S.R., Ghana, South and South West Africa, Madagascar, Australia, New Zealand, Great Britain, Japan etc. An attempt will be made to summarize the pertinent data on these metamorphosed sedimentary formations so as to establish the role of original bulk composition of the sediments, transformation and reaction of phases at ele- vated temperature and varying oxygen and carbon dioxide fugacities in determin- ing the mineral assemblages in these deposits. -
Palomar Gem & Mineral Club Newsletter
Palomar Gem & Mineral Club Newsletter August 2016 Volume 57 Issue 07 PGMC Annual Picnic We had our annual summer picnic last month at Jesmond Dene Park. As always Moni did a fine job of coordinating the event which included great food brought by everyone as well as a good time of comparing the fine rocks and gems we have found. We had a great slab swap between our members and everyone seemed to have a good time. As summer ends and we get ready to ramp up again, we hope everyone had a safe and productive summer. August is usually a down month for PGMC so that any specialty classes can take place at the shop and folks can go on vacation. We look forward to seeing everyone at the September meeting. Check out the rest of the newsletter for more information about September’s meeting as well as upcoming class schedules. We begin classes this week! 1 Textured Metal Class Come and join in the fun, learning to texture metal and make one-of-kind earrings (3 to 4 pairs) or a bracelet). They are great gifts. You may also learn how to make your own ear wires. Instructors: Diane Hall & Annie Heffner Location: Club Shop Dates: November 20, 2016 Time: 10am-4pm Fee: $35 plus supply cost (club membership required - $25 fee for single membership). You will need about 1 ounce of silver or copper sheet, which we will purchase for every one who is signed up by November 11th. Sign ups after that will need to provide their own material. -
Age and Origin of Silicocarbonate Pegmatites of the Adirondack Region
minerals Article Age and Origin of Silicocarbonate Pegmatites of the Adirondack Region Jeffrey Chiarenzelli 1,*, Marian Lupulescu 2, George Robinson 1, David Bailey 3 and Jared Singer 4 1 Department of Geology, St. Lawrence University, Canton, NY 13617, USA 2 New York State Museum, Research and Collections, Albany, NY 12230, USA 3 Geosciences Department, Hamilton College, Clinton, NY 13323, USA 4 Earth and Environmental Sciences, Rensselaer Polytechnic Institute, Rensselaer, NY 12180, USA * Correspondence: [email protected]; Tel.: +1-315-229-5202 Received: 24 July 2019; Accepted: 19 August 2019; Published: 23 August 2019 Abstract: Silicocarbonate pegmatites from the southern Grenville Province have provided exceptionally large crystal specimens for more than a century. Their mineral parageneses include euhedral calc–silicate minerals such as amphibole, clinopyroxene, and scapolite within a calcite matrix. Crystals can reach a meter or more in long dimension. Minor and locally abundant phases reflect local bedrock compositions and include albite, apatite, perthitic microcline, phlogopite, zircon, tourmaline, titanite, danburite, uraninite, sulfides, and many other minerals. Across the Adirondack Region, individual exposures are of limited aerial extent (<10,000 m2), crosscut metasedimentary rocks, especially calc–silicate gneisses and marbles, are undeformed and are spatially and temporally associated with granitic pegmatites. Zircon U–Pb results include both Shawinigan (circa 1165 Ma) and Ottawan (circa 1050 Ma) intrusion ages, separated by the Carthage-Colton shear zone. Those of Shawinigan age (Lowlands) correspond with the timing of voluminous A-type granitic magmatism, whereas Ottawan ages (Highlands) are temporally related to orogenic collapse, voluminous leucogranite and granitic pegmatite intrusion, iron and garnet ore development, and pervasive localized hydrothermal alteration. -
Jacobsite from the Tamworth District of New South Wales
538 Jacobsite from the Tamworth district of New South Wales. By F .L. STILLWELL, D.Sc., and A. B. EDWAP~DS,D.Sc., Ph.D., D.I.C. Commonwealth Scientific and Industrial Organization, Melbourne. [Taken as read November 2, 1950.] WO new occurrences of the rare manganese mineral jacobsite T (MnF%0~) have come to light in the course of mineragraphic studies carried out as part of the research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research Organization. The jacobsite occurs as a constituent of small bodies of high-grade manganese ore at Weabonga, near Danglemah, and at the Mount Sally mine, about 6 miles west of Danglemah, both in the Tam- worth district of New South Wales. The deposits occur in altered sediments, within a mile or two of a granite contact. 1 They are irregular lenticular veins ranging from a few inches to several feet in thickness, between altered slate walls. The veins do not exceed a length of 200-300 feet. The lode material consists of manganese oxides, chiefly psilomelane and pyrolusite, associated with quartz, rhodonite, and iron oxide. The manganese oxides are mainly supergene, and although the deposits are of high grade near the surface, it is doubtful whether they can be worked below the depths of 50- 60 feet, owing to the increase in the amount of rhodonite and quartz relative to manganese oxides at this depth. In the Weabonga ore the jacobsite occurs as narrow seams and lenticles, about 0.5 cm. across, and 3.0 cm. long enclosed in, and partly replaced by, pyrolusite and psilomelane. -
Renowned for His Iconic Designs and Breathtaking Gem Collections, Harry Winston Was a Man Who Knew the True Value of a Diamond
A BRILLIANT LEGACY Renowned for his iconic designs and breathtaking gem collections, Harry Winston was a man who knew the true value of a diamond. BY ALLISON HATA 54 A diamond is anything but just another stone. Highly coveted, precious and exceedingly rare, diamonds can take on different meanings: a symbol of status, a statement of love or a sign of purity. “Diamonds are a physical connection to [the earth] other than our feet on the ground,” says Russell Shor, a senior industry analyst for the Gemologist Institute of America. “When the earth was young and there was volcanic mass seething inside—this is how diamonds were formed. Diamonds connect us to that.” One man understood this intrinsic connection and dedicated his life to bringing the world closer to the precious gem through his jewelry designs and generous gifts to national institu- tions. Known as the “king of dia- monds,” the late Harry Winston was the first American jeweler to own and cut some of the most iconic stones in history, in addi- tion to setting a new standard for jewelry that showcases a gem’s natural beauty. Born more than a century ago, the young Winston—the son of a small jewelry shop owner—demonstrated a natural instinct for examining diamonds and precious gems. In subsequent years, he cultivated this talent to become one of the most prominent diamond merchants and designers of his time. His legacy lives on through the house of Harry Winston, which pairs his classic vision with a contemporary sensi- bility to create modern pieces that still grace the red carpet today. -
The Tubesat Launch Vehicle
TubeSat and NEPTUNE 30 Orbital Rocket Programs Personal Satellites Are GO! Interorbital Systems www.interorbital.com About Interorbital Corporation Founded in 1996 by Randa and Roderick Milliron, incorporated in 2001 Located at the Mojave Spaceport in Mojave, California 98.5% owned by R. and R. Milliron 1.5% owned by Eric Gullichsen Initial Starting Technology Pressure-fed liquid rocket engines Initial Mission Low-cost orbital and interplanetary launch vehicle development Facilities 6,000 square-foot research and development facility Two rocket engine test sites at the Mojave Spaceport Expert engineering and manufacturing team Interorbital Systems www.interorbital.com Core Technical Team Roderick Milliron: Chief Designer Lutz Kayser: Primary Technical Consultant Eric Gullichsen: Guidance and Control Gerard Auvray: Telecommunications Engineer Donald P. Bennett: Mechanical Engineer David Silsbee: Electronics Engineer Joel Kegel: Manufacturing/Engineering Tech Jacqueline Wein: Manufacturing/Engineering Tech Reinhold Ziegler: Space-Based Power Systems E. Mark Shusterman,M.D. Medical Life Support Randa Milliron: High-Temperature Composites Interorbital Systems www.interorbital.com Key Hardware Built In-House Propellant Tanks: Combining state-of-the-art composite technology with off-the-shelf aluminum liners Advanced Guidance Hardware and Software Ablative Rocket Engines and Components GPRE 0.5KNFA Rocket Engine Test Manned Space Flight Training Systems Rocket Injectors, Valves Systems, and Other Metal components Interorbital Systems www.interorbital.com Project History Pressure-Fed Rocket Engines GPRE 2.5KLMA Liquid Oxygen/Methanol Engine: Thrust = 2,500 lbs. GPRE 0.5KNFA WFNA/Furfuryl Alcohol (hypergolic): Thrust = 500 lbs. GPRE 0.5KNHXA WFNA/Turpentine (hypergolic): Thrust = 500 lbs. GPRE 3.0KNFA WFNA/Furfuryl Alcohol (hypergolic): Thrust = 3,000 lbs. -
Blue Diamond Prices Are on the Rise
This copy is for your personal, non-commercial use only. To order presentation-ready copies for distribution to your colleagues, clients or customers visit http://www.djreprints.com. https://www.barrons.com/articles/blue-diamond-prices-are-on-the-rise-1518037930 Blue Diamond Prices Are on the Rise By Ariel R. Shapiro Feb. 7, 2018 4:12 p.m. ET The fancy color diamond market is on the upswing, according to a report, with blue diamonds seeing the largest gains. Blue diamonds saw a 5.9% increase in value in the fourth quarter of 2017 in a year-over-year comparison, according to data published on Feb. 1 by the Fancy Color Research Foundation (FCRF). Pink and yellow diamond prices decreased slightly in the same period, at 0.8% and 1.8%, respectively. The market overall was up 0.1%. A fancy vivid blue diamond ring (est. $14-18 million) goes on view at Sotheby's on Oct. 13, 2017 in London. ILLUSTRATION: GETTY IMAGES FOR SOTHEBY'S In November 2017, Christie’s sold a 8.67-carat fancy intense blue diamond ring in Geneva, Switzerland for $13.2 million. The reason for this disparity has less to do with demand, than it does with the rarity of the stone, says FCRF Chairman Eden Rachminov. Demand for yellow and pink diamonds is actually higher, but the amount of blue diamonds being mined is decreasing. “Almost nothing is coming out of the ground,” he says. Pink diamonds have seen the highest gains in the last 13 years with an overall appreciation of 361.9%, according to FCRF’s index, which is compiled through survey data provided by manufacturers and brokers. -
Pearl Accessories Operator's Manual
Pearl® Trilogy Accessories Manual CE Marking: This product (model number 5700-DS) is a CE-marked product. For conformity information, contact LI-COR Support at http://www.licor.com/biotechsupport. Outside of the U.S., contact your local sales office or distributor. Notes on Safety LI-COR products have been designed to be safe when operated in the manner described in this manual. The safety of this product cannot be guaranteed if the product is used in any other way than is specified in this manual. The Pearl® Docking Station and Pearl Clean Box is intended to be used by qualified personnel. Read this entire manual before using the Pearl Docking Station and Pearl Clean Box. Equipment Markings: The product is marked with this symbol when it is necessary for you to refer to the manual or accompanying documents in order to protect against damage to the product. The product is marked with this symbol when a hazardous voltage may be present. Manual Markings: WARNING Warnings must be followed carefully to avoid bodily injury. CAUTION Cautions must be observed to avoid damaging your equipment. NOTE Notes contain additional information and useful tips. IMPORTANT Information of importance to prevent procedural mistakes in the operation of the equipment or related software. Failure to comply may result in a poor experimental outcome but will not cause bodily injury or equipment damage. Federal Communications Commission Radio Frequency Interference Statement WARNING: This equipment generates, uses, and can radiate radio frequency energy and if not installed in accordance with the instruction manual, may cause interference to radio communications. -
Trade Studies Towards an Australian Indigenous Space Launch System
TRADE STUDIES TOWARDS AN AUSTRALIAN INDIGENOUS SPACE LAUNCH SYSTEM A thesis submitted for the degree of Master of Engineering by Gordon P. Briggs B.Sc. (Hons), M.Sc. (Astron) School of Engineering and Information Technology, University College, University of New South Wales, Australian Defence Force Academy January 2010 Abstract During the project Apollo moon landings of the mid 1970s the United States of America was the pre-eminent space faring nation followed closely by only the USSR. Since that time many other nations have realised the potential of spaceflight not only for immediate financial gain in areas such as communications and earth observation but also in the strategic areas of scientific discovery, industrial development and national prestige. Australia on the other hand has resolutely refused to participate by instituting its own space program. Successive Australian governments have preferred to obtain any required space hardware or services by purchasing off-the-shelf from foreign suppliers. This policy or attitude is a matter of frustration to those sections of the Australian technical community who believe that the nation should be participating in space technology. In particular the provision of an indigenous launch vehicle that would guarantee the nation independent access to the space frontier. It would therefore appear that any launch vehicle development in Australia will be left to non- government organisations to at least define the requirements for such a vehicle and to initiate development of long-lead items for such a project. It is therefore the aim of this thesis to attempt to define some of the requirements for a nascent Australian indigenous launch vehicle system. -
A Survey of the Gemstone Resources of China
A SURVEY OF THE GEMSTONE RESOURCES OF CHINA By Peter C. Keller and Wang Fuquan The People's Republic of China has recently hina has historically been a land of great mystery, placed a high priority on identifying and C with natural resources and cultural treasures that, developing its gemstone resources. Initial until recently, were almost entirely hidden from the out- exploration by teams of geologists side world. From the point of view of the geologist and throughout China has identified many gemologist, one could only look at known geological maps deposits with significant potential, of this huge country and speculate on the potential impact including amher, cinnabar, garnets, blue sapphires, and diamonds. Small amounts of China would have on the world's gem markets if its gem ruby have' qlso been found. Major deposits resources were ever developed to their full potential. of nephriteyade as well as large numbers of During the past few years, the government of the Peo- gem-bearing pegmatite dilces have been ple's Republic of China (P.R.C.)has opened its doors to the identified.Significant deposits of peridot outside world in a quest for information and a desire for are crirrently being exploited from Hebei scientific and cultural cooperation. It was in this spirit of Province. Lastly, turqrloise rivaling the cooperation that a week-long series of lectures on gem- finest Persian material has been found in stones and their origins was presented by the senior author large quantities in Hubei and Shaanxi and a colleague to over 100 geologists from all over China Provinces. -
Study of a 100Kwe Space Reactor for Exploration Missions
Preliminary study of a 100 kWe space reactor concept for exploration missions Elisa CLIQUET, Jean-Marc RUAULT 1), Jean-Pierre ROUX, Laurent LAMOINE, Thomas RAMEE 2), Christine POINOT-SALANON, Alexey LOKHOV, Serge PASCAL 3) 1) CNES Launchers Directorate,Evry, France 2) AREVA TA, Aix en Provence, France 3) CEA DEN/DM2S, F-91191 Gif-sur-Yvette, France NETS 2011 Overview ■ General context of the study ■ Requirements ■ Methodology of the study ■ Technologies selected for final trade-off ■ Reactor trade-off ■ Conversion trade-off ■ Critical technologies and development philosophy ■ Conclusion and perspectives CNES Directorate of Launchers Space transportation division of the French space agency ■ Responsible for the development of DIAMANT, ARIANE 1 to 4, ARIANE 5, launchers ■ System Architect for the Soyuz at CSG program ■ Development of VEGA launcher first stage (P80) ■ Future launchers preparation activities Multilateral and ESA budgets • To adapt the current launchers to the needs for 2015-2020 • To prepare launcher evolutions for 2025 - 2030, if needed • To prepare the new generation of expandable launchers (2025-2030) • To prepare the long future after 2030 with possible advanced launch vehicles ■ Future space transportation prospective activities, such as Exploration needs (including in particular OTV missions) Advanced propulsion technologies investigation General context ■ Background Last French studies on space reactors : • ERATO (NEP) in the 80’s, • MAPS (NTP) in the 90’s • OPUS (NEP) 2002-2004 ■ Since then Nuclear safe orbit