Are Slightly Uneven Earrings Noticeable
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Magnetite and Hematite Intheiron Ores of the Kiruna Type and Some Other Iron Ore Types
SERIE C NR 625 AVHANDLINGAR OCH UPPSATSER ARSBOK 6 1 NR 10 RUDYARD FRIETSCH THE RELATIONSHIP BETWEEN MAGNETITE AND HEMATITE INTHEIRON ORES OF THE KIRUNA TYPE AND SOME OTHER IRON ORE TYPES STOCKHOLM 1967 SVERIGES GEOLOGISKA UNDERSOKNING SERIE C NR 625 ARSBOK 61 NR 10 RUDYARD FKIETSCH THE RELATIONSHIP BETWEEN MAGNETITE AND HEMATITE IN THE IRON ORES OF THE KIRUNA TYPE AND SOME OTHER IRON ORE TYPES STOCKHOLM 1967 Manuscript received May 8th, 1967 Editor: Per H. Lundegårdh Stockholm 1967 Kungl. Boktryckeriet P. A. Norstedt & Söner CONTENTS Abstracc ................................. Introdiiction ................................ The relationship between magnetite and hernatite in kon ores of the Kiruna type ... Northern Sweden ............................ Central Sweden ............................ Chile .................................. Mexico ................................. United States ............................. The formation of'hematite in iron ores of the Kiruna type ............ Examples of the occurrence of hematite in connection with metasomalic processes ... The relationship between magnetite and hematite in ~henon-apatitic irvri ores of Central Sweden .................................. Conclusions ................................ Acknowledgements ............................. References ................................. 7 1.670383 . SGU. Frietsch ABSTRACT I11 the magmatic iron ores of thc Kiruna type the primary iron oxide is inostly magnetite. Hematite is rather common and except when clue to superficial weathering is a later metasomatic alteration of the magnetite. The alteration in the wall-rock (and to a less exteiit in the orc) has given rise to new minerals, e. g. quarte, muscovite, chlorite, calcite, clay minerals and small amounts of tourmaline, fluoritc, barite, allanite and zircoii. It is a later phase of the main ore- forming process. The tcmpcraturc at which the alteration took place is, on account of the niiner- al paragenesis in the altered wall-rock, believed to have been moderate tc. -
A Preliminary Study on the Interfacial Strength of Red Abalone
University of Vermont ScholarWorks @ UVM Graduate College Dissertations and Theses Dissertations and Theses 2016 A Preliminary Study On The nI terfacial Strength Of Red Abalone Saleh Jaman Alghamdi University of Vermont Follow this and additional works at: https://scholarworks.uvm.edu/graddis Part of the Civil Engineering Commons Recommended Citation Alghamdi, Saleh Jaman, "A Preliminary Study On The nI terfacial Strength Of Red Abalone" (2016). Graduate College Dissertations and Theses. 633. https://scholarworks.uvm.edu/graddis/633 This Thesis is brought to you for free and open access by the Dissertations and Theses at ScholarWorks @ UVM. It has been accepted for inclusion in Graduate College Dissertations and Theses by an authorized administrator of ScholarWorks @ UVM. For more information, please contact [email protected]. A PRELIMINARY STUDY ON THE INTERFACIAL STRENGTH OF RED ABALONE A Thesis Presented by Saleh J Alghamdi to The Faculty of the Graduate College of The University of Vermont In Partial Fulfillment of the Requirements for the Degree of Master of Science Specializing in Civil Engineering October, 2016 Defense Date: June 14, 2016 Thesis Examination Committee: Ting Tan, Ph.D, Advisor Jie Yang, Ph.D., Chairperson George Pinder, Ph.D. Cynthia J. Forehand, Ph.D., Dean of the Graduate College Abstract Nacre is a hierarchical material found within the tough shells of red abalone. Despite being composed of calcium carbonate, nacre exhibits remarkable mechanical properties resulting from the nanoscale brick-and-mortar structure made from aragonite polygons. The objective of this research is to elucidate the toughening mechanisms associated with the interfacial resistance of red abalone. -
Pearls and Organic Gemstones
Pearls and Organic Gemstones INTRODUCTION Pearls were probably the first discovered gems of significance. Because they need no cutting or treatment to enhance their beauty and are rare natural occurrences, they have most likely always been highly esteemed. Organic gemstones are anything created by living processes. We have looked at amber in the past, but bone, teeth (such as ivory), and shells all have some value and are used today as gemstones. Pearls in General A pearl is grown by a mollusk (a bivalve such as a clam, oyster, or mussel or snail [single shell = valve]) in response to an irritant. Bivalves (two shelled mollusks) that secrete pearls live in both fresh‐ and saltwater. The irritant in most cases is a parasite (though it could be a grain of sand or other object). The parasite, a worm or other creature, is walled off by a secretion of calcium carbonate and protein. The calcium carbonate is the same as the inorganic material that makes stalactites in caves, and the protein is called conchiolin. The combination of these two substances (calcium carbonate and protein) makes the pearl's nacre (Nacre is also called mother of pearl). The nacre is a lustrous deposit around the irritant and forms concentric layers (overlapping circles). Many concentric layers of nacre build up over a period of a few years creating a pearl. The internal pattern is much like that seen in a jawbreaker. The layers create a sheen or luster that has iridescence and is described as both pearly luster and if colors of the rainbow are present, the pearl's orient. -
Colored Gemstones Cultured Pearls
Cultured Pearls Colored Gemstones Diamond Council of America ©2016 Cultured Pearls In This Lesson: •A World Apart • Pearl Traditions • Natural Pearls • Cultured Pearls •Value Factors •Product Highlights • Culturing Sales A WORLD APART In Lesson 1 you learned that any kind of gem except diamond is considered a colored gem. Although pearls are included in that broad classification, they really belong to a world apart. Most customers recognize this instinctively, sensing a special appeal about pearls. There are several themes you can use in a sales presenta- tion to evoke or enhance pearl’s separate place in the gem kingdom: • Pearls are born in water. This intuitive contrast with other gems, which are dug from the ground, gives pearls an aura of gentleness, freshness, and fluid grace. • Pearls originate from life. While most gems are minerals produced by inanimate geology, pearls are organic. They come from living beings. Much of pearls’ mystique arises from this connection. • Pearls possess a beauty that’s all their own. Most gems depend on cutting or carving to reveal their charms, but pearls emerge gleaming from their shells. Cultured pearls are born in water and originate from living organisms. They Though certain factors of pearl value are comparable are natural in their beauty and classic to those of other gems, key considerations are unique. as a gem. Colored Gemstones 5 1 Cultured Pearls Cultured pearls are modern forms of a classic gem. They ® combine Nature’s creative power with human art and JA SPC SKILLS If you’re participating in the JA® science. You could even say that cultured pearls show how Sales Professional Certification people can work with the environment to make age-old Program™, this lesson presents infor- mation related to the following Skill beauty available now, and for future generations as well. -
Tourmaline Announces Formation of Topaz Energy, Unlocking Value in Tourmaline's Significant Asset Base
NOT FOR DISTRIBUTION IN THE UNITED STATES OR DISSEMINATION OVER UNITED STATES NEWSWIRE SERVICES. NEWS RELEASE OCTOBER 10, 2019 TOURMALINE ANNOUNCES FORMATION OF TOPAZ ENERGY, UNLOCKING VALUE IN TOURMALINE'S SIGNIFICANT ASSET BASE Calgary, Alberta - Tourmaline Oil Corp. (TSX:TOU) ("Tourmaline") is pleased to announce the formation of Topaz Energy Corp. (“Topaz”), a new private royalty and infrastructure energy company. Tourmaline will sell to Topaz: a royalty interest on Tourmaline lands, a non-operated interest in two of Tourmaline‘s existing 19 natural gas processing plants, and a contracted interest in a portion of Tourmaline‘s current third-party revenue for total cash and share consideration of $775 million. Topaz will be a low-risk, high-distribution, hybrid royalty and infrastructure energy company with long-term growth plans. Topaz will be capitalized initially with a $150 to $200 million third-party equity private placement, with Tourmaline retaining a 75% to 81% equity ownership interest. Tourmaline intends to reduce a portion of its ownership as Topaz participates in future acquisition activities and an anticipated Topaz public liquidity event in 2020. The initial acquisition from Tourmaline is expected to generate approximately $90 million in revenue(1) in 2020, of which it is anticipated approximately 75% will be paid out in quarterly dividends ($0.80 per share annually, 8% yield). The assets to be acquired from Tourmaline will consist of three components: 1. A gross overriding royalty (“GORR”) on natural gas, oil, and condensate production on 100% of Tourmaline’s existing lands (approximately 2.2 million net acres). 2. A non-operated 45% working interest in two natural gas processing plants underpinned by long-term take- or-pay commitments from Tourmaline. -
Lapidary Journal Jewelry Artist March 2012
INDEX TO VOLUME 65 Lapidary Journal Jewelry Artist April 2011-March 2012 INDEX BY FEATURE/ Signature Techniques Part 1 Resin Earrings and Pendant, PROJECT/DEPARTMENT of 2, 20, 09/10-11 30, 08-11 Signature Techniques Part 2 Sagenite Intarsia Pendant, 50, With title, page number, of 2, 18, 11-11 04-11 month, and year published Special Event Sales, 22, 08-11 Silver Clay and Wire Ring, 58, When to Saw Your Rough, 74, 03-12 FEATURE ARTICLES Smokin’*, 43, 09/10-11 01/02-12 Argentium® Tips, 50, 03-12 Spinwheel, 20, 08-11 Arizona Opal, 22, 01/02-12 PROJECTS/DEMOS/FACET Stacking Ring Trio, 74, Basic Files, 36, 11-11 05/06-11 DESIGNS Brachiopod Agate, 26, 04-11 Sterling Safety Pin, 22, 12-11 Alabaster Bowls, 54, 07-11 Create Your Best Workspace, Swirl Step Cut Revisited, 72, Amethyst Crystal Cross, 34, 28, 11-11 01/02-12 Cut Together, 66, 01/02-12 12-11 Tabbed Fossil Coral Pendant, Deciphering Chinese Writing Copper and Silver Clay 50, 01/02-12 Linked Bracelet, 48, 07-11 12, 07-11 Stone, 78, 01/02-12 Torch Fired Enamel Medallion Site of Your Own, A, 12, 03-12 Easier Torchwork, 43, 11-11 Copper Wire Cuff with Silver Necklace, 33, 09/10-11 Elizabeth Taylor’s Legendary Wire “Inlay,” 28, 07-11 Trillion Diamonds Barion, 44, SMOKIN’ STONES Jewels, 58, 12-11 Coquina Pendant, 44, 05/06-11 Alabaster, 52, 07-11 Ethiopian Opal, 28, 01/02-12 01/02-12 Turquoise and Pierced Silver Ametrine, 44, 09/10-11 Find the Right Findings, 46, Corrugated Copper Pendant, Bead Bracelet – Plus!, 44, Coquina, 42, 01/02-12 09/10-11 24, 05/06-11 04-11 Fossilized Ivory, 24, 04-11 -
Does Abalone Nacre Form by Heteroepitaxial Nucleation Or by Growth Through Mineral Bridges?
Chem. Mater. 1997, 9, 1731-1740 1731 Does Abalone Nacre Form by Heteroepitaxial Nucleation or by Growth through Mineral Bridges? Tilman E. Scha¨ffer,*,† Cristian Ionescu-Zanetti,†,⊥ Roger Proksch,† Monika Fritz,†,‡ Deron A. Walters,† Nils Almqvist,†,| Charlotte M. Zaremba,§,⊥ Angela M. Belcher,‡,§ Bettye L. Smith,†,⊥ Galen D. Stucky,§,⊥ Daniel E. Morse,‡,⊥ and Paul K. Hansma†,⊥ Department of Physics, University of California, Santa Barbara, California 93106; Marine Biotechnology Center and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, California 93106; Department of Chemistry, University of California, Santa Barbara, California 93106; Materials Research Laboratory, University of California, Santa Barbara, California 93106; and Department of Physics, Luleå University of Technology, S-97187 Luleå, Sweden Received August 12, 1996. Revised Manuscript Received June 10, 1997X We present experimental support for a model of abalone nacre growth that is based on mineral bridges between successive aragonite tablets rather than on heteroepitaxial nucleation. Interlamellar sheets of organic polymers delineate the aragonite tablets but allow the tablets to grow mineral bridges through pores in the sheets. Atomic force microscope images of interlamellar organic sheets from flat pearls made by Haliotis rufescens (red abalone; marine gastropod mollusk) reveal a fibrous core and holes of 5-50 nm in diameter. Scanning ion conductance microscopy shows that these holes are actually pores through the interlamellar sheets. With the help of statistical analysis we can associate the pore-to-pore spacings in the interlamellar sheets with the observed offsets of successive nacre tablets. These results, supplemented by AFM, SEM, and TEM images, support and extend the model of biofabrication of gastropod nacre which is based on mineral bridges between the aragonite tablets. -
DIAMOND Natural Colorless Type Iab Diamond with Silicon-Vacancy
Editors Thomas M. Moses | Shane F. McClure DIAMOND logical and spectroscopic features con- Natural Colorless Type IaB firmed the diamond’s natural origin, – Diamond with Silicon-Vacancy despite the occurrence of [Si-V] emis- Defect Center sions. No treatment was detected. Examination of this stone indicated The silicon-vacancy defect, or [Si-V]–, that the [Si-V]– defect can occur, albeit is one of the most important features rarely, in multiple types of natural dia- in identifying CVD synthetic dia- monds. Therefore, all properties should monds. It can be effectively detected be carefully examined in reaching a using laser photoluminescence tech- conclusion when [Si-V]– is present. nology to reveal sharp doublet emis- sions at 736.6 and 736.9 nm. This Carmen “Wai Kar” Lo defect is extremely rare in natural dia- monds (C.M. Breeding and W. Wang, “Occurrence of the Si-V defect center Figure 1. Emissions from the Screening of Small Yellow Melee for in natural colorless gem diamonds,” silicon-vacancy defect at 736.6 and Treatment and Synthetics Diamond and Related Materials, Vol. 736.9 nm were detected in this Diamond treatment and synthesis 17, No. 7–10, pp. 1335–1344) and has 0.40 ct type IaB natural diamond. have undergone significant develop- been detected in very few natural type ments in the last decade. During this IIa and IaAB diamonds over the past showed blue fluorescence with natural time, the trade has grown increasingly several years. diamond growth patterns. These gemo- concerned about the mixing of treated Recently, a 0.40 ct round brilliant diamond with D color and VS2 clarity (figure 1) was submitted to the Hong Figure 2. -
PDF Red List of Colombian Cultural Objects at Risk
RED LIST OF COLOMBIAN CULTURAL OBJECTS AT RISK BIAN T OF COLOM D LIS T RISK RE OBJECTS A CULTURAL S T E Illegal excavationL of archIaeological sites ( guaquería ) severs the connection between an object and its context, preventing properG identificEation of the Rartefact aOnd diminiUshing its cultural meaning. As a result, the scientific study of looted sites is very limited since information essential for reconstructing ways of life has been destroyed. Thefts from museums, churches, libraries and archives irreparably damage the integrity of Three thousand pre-Columbian items seized in 2004, collections, leaving gaps that distort the historical by the Administrative Department of Security, record. from a U.S. trafficker living in Colombia. © Instituto Colombiano de Antropología e Historia (ICANH) Colombia’s National Campaign against Illicit Trafficking in Cultural Property seeks to protect Colombian heritage from such criminal acts, implementing its strategies through national and international agreements. It provides both courses and on-line training dedicated to spreading knowledge about movable cultural heritage, and to enhancing its appreciation, conservation and use. It also aims to strengthen legislation, and to publish guides, posters and informative brochures. ICOM contributes to these efforts with this Red List . If you suspect that a cultural object from Colombia may be stolen, looted or illegally exported, please contact: Ministry of Culture, Ministry of Foreign Affairs, National Police, Cultural Heritage Directorate of Heritage -
DNA Fingerprinting of Pearls, Corals and Ivory: a Brief Review of Applications in Gemmology Laurent E
FEATURE ARTICLE DNA Fingerprinting of Pearls, Corals and Ivory: A Brief Review of Applications in Gemmology Laurent E. Cartier, Michael S. Krzemnicki, Bertalan Lendvay and Joana B. Meyer ABSTRACT: This article reviews the extraction of DNA (deoxyribonucleic acid) from biogenic gem materials (pearls, corals and ivory) for determining species identification and geographic/genetic origin. We describe recent developments in the methodology adapted for gem samples that is minimally destructive, as well as the successful DNA fingerprinting of cultured pearls from various Pinctada molluscs to identify their species. The DNA analysis methods presented here can also potentially be used for fingerprinting corals and ivory. The Journal of Gemmology, 36(2), 2018, pp. 152–160 http://dx.doi.org/10.15506/JoG.2018.36.2.152 © 2018 The Gemmological Association of Great Britain iogenic gems—often called ‘organic gems’ which consists of CaCO3 as well as protein, glycosamino- (see Galopim de Carvalho, 2018, for a recent glycans and proteoglycans (Debreuil et al., 2012). They can discussion of terminology)—are some of the be coloured by carotenoids and other types of pigments. oldest-used gem materials and have been Finally, elephant ivory from African (Loxodonta spp.) Bcherished since pre-history (Hayward, 1990; Tsounis et and Asian (Elephas spp.) elephant tusks is comprised al., 2010; Charpentier et al., 2012). Rather than having a of collagen and carbonate-rich hydroxyapatite (dahllite, geological origin, these gem materials—such as pearls, Ca10[PO4]6[CO3] • H2O; Edwards et al., 2006). Ivory precious corals and ivory (e.g. Figure 1)—are products can be found in a large number of animal species, of of biomineralisation processes in which living animals which elephant ivory is the most studied due to its value, produce mineral substances (e.g. -
Gem Wealth of Tanzania GEMS & GEMOLOGY Summer 1992 Fipe 1
By Dona M.Dirlarn, Elise B. Misiorowski, Rosemaiy Tozer, Karen B. Stark, and Allen M.Bassett The East African nation of Tanzania has he United Republic of Tanzania, the largest of the East great gem wealth. First known by Western- 1African countries, is composed of mainland Tanzania and ers for its diamonds, Tanzania emerged in the island of Zanzibar. 1t is regarded by many as the birthplace the 1960s as a producer of a great variety of of the earliest ancestors of Homo sapiens. To the gem indus- other gems such as tanzanite, ruby, fancy- try, however, Tanzania is one of the most promising fron- colored sapphire, garnet, and tourmaline; to date, more than 50 gem species and vari- tiers, with 50 gem species and varieties identified, to date, eties have been produced. As the 1990s from more than 200 occurrences. begin, De Beers has reinstated diamond "Modem" mining started in the gold fields of Tanzania in exploration in Tanzania, new gem materials the late 1890s (Ngunangwa, 19821, but modem diamond min- such as transparent green zoisite have ing did not start until 1925, and nearly all mining of colored appeared on the market, and there is stones has taken place since 1950. Even so, only a few of the increasing interest in Tanzania's lesser- gem materials identified have been exploited to any significant known gems such as scapolite, spinel, and extent: diamond, ruby, sapphire, purplish blue zoisite (tan- zircon. This overview describes the main zanite; figure l),and green grossular [tsavorite)and other gar- gems and gem resources of Tanzania, and nets. -
Vintage Pearl Necklace with Diamond Clasp, NK-3522 the Diamond
Vintage Pearl Necklace with Diamond Clasp, NK-3522 The diamond-accented clasp in this vintage pearl necklace is dainty and elegant. Strung with round Akoya saltwater peals, this vintage jewelry piece secures with a platinum and 14k white gold navette-shaped clasp. Old European cut diamonds are arranged in a flirty bowtie down the center of the clasp. Details: Platinum and 14k white gold. Old European cut diamonds; 0.51 carats. Akoya saltwater pearls. Vintage, Circa 1930s Item # nk3522 Metal platinum and 14k white gold Circa 1930s Condition Very Good Diamond cut or shape old European cut Diamond carat weight 0.39 Diamond mm measurements 4.4 x 2.76 Diamond color G Diamond clarity SI1 Diamond # of stones 1 Diamond2 cut or shape old European Diamond2 carat weight 0.12 Diamond2 mm measurements 2.5 Diamond2 color E Diamond2 clarity SI1 and I1 Diamond2 # of stones 2 Number of pearls 52 Pearl shape near round Pearl size 7.5 - 8.2 Pearl color silver white Pearl overtone rose Other pearl info Akoya saltwater pearls, bright luster, slightly blemished complexion, adequate nacre, excellent matching Necklace length 460 mm [17.94 in] Clasp details Navette shaped clasp measuring 13x7x5mm. The clasp is platinum and the tongue is 14k white gold. Important Jewelry Information Each antique and vintage jewelry piece is sent off site to be evaluated by an appraiser who is not a Topazery employee and who has earned the GIA Graduate Gemologist diploma as well as the title of AGS Certified Gemologist Appraiser. The gemologist/appraiser's report is included on the Detail Page for each jewelry piece.