Distinguishing Natural Diamonds from Synthetic Diamonds and Diamond

Total Page:16

File Type:pdf, Size:1020Kb

Distinguishing Natural Diamonds from Synthetic Diamonds and Diamond Synthetic Diamond Identification About GIA Knowing the Difference Because of the contrasting conditions of natural Established in 1931, GIA has studied the scientific Natural diamonds have long fascinated mankind and artificial formation, synthetic diamonds properties of gems, developing new methods of with their unique physical and visual properties. display several features which allow them to be identifying natural, synthetic and treated gemstones. Distinguishing Features such as exceptional hardness, durability, gemologically distinguished from natural diamonds. This research serves to protect all who buy and sell light reflectivity (brilliance) and dispersion (fire) These include visual characteristics such as color gems by ensuring accurate and unbiased standards Natural Diamonds from distinguish them from other gems. The beauty and zoning, dark metallic inclusions, weak strain for determining and describing gem quality. GIA universal appeal of natural diamonds come at a patterns and distinctive patterns and colors of research findings are incorporated into its educational Synthetic Diamonds and price, as the recovery and fashioning of such rare ultraviolet fluorescence. Because they represent programs, published in professional journals, used for Diamond Simulants gems are challenging. For decades, researchers types of diamonds that are rare in nature, synthetic developing practical instruments and tools and applied have sought alternatives by creating less expensive diamonds also possess additional features that in grading and identification services every day. “look-alikes” in the form of simulants and, more can be detected with gemological instruments. recently, “duplicates” with synthetic diamonds. To learn more about diamond identification and Though such attempts by man to recreate the Decades of research, in addition to the use and GIA laboratory services, and to view past issues of properties and structure of natural diamonds are development of advanced scientific instrumentation, Gems & Gemology, visit GIA.edu nothing new, a rapid increase in synthetic diamond enable GIA to accurately identify synthetic growth technology over the past decade has led diamonds. GIA’s Diamond Check™ and recent to real concerns regarding their identification. introduction of a fully automated Melee Analysis Service allow for fast and accurate separation Fortunately, GIA has followed the developments of of loose natural diamonds from loose synthetics synthetic diamonds for more than 60 years. This and simulants. The challenge to develop a similar continuum—combined with fundamental research method for analysis of mounted stones is more on tens of millions of natural diamonds—allows complex due to coverage from metal settings. GIA to accurately identify synthetic diamonds. Information on synthetic diamond identification In order to protect yourself and your clients has been published extensively in GIA’s peer- against misrepresentations and misconceptions reviewed Gems & Gemology over the last 30 years. surrounding natural diamonds, synthetic diamonds, and diamond simulants, it is important that you understand the differences among them and the means of their identification. Unlike diamond simulants, which can be recognized by using standard gem testing, synthetic diamonds have essentially the same chemical composition and crystal structure as natural diamonds, but are made in laboratories—not grown in the earth. Because their optical and physical properties are nearly identical to natural diamonds’, identifying synthetic diamonds is complex. However, because of their artificial growth environments, synthetic diamonds exhibit several diagnostic features that allow for their detection in gemological laboratories. ™ The World’s Foremost Authority in Gemology synthetic diamond (middle) and simulant (bottom). diamond (top), image: Natural cover Front COPYRIGHT ©2016 GEMOLOGICAL INSTITUTE OF AMERICA, INC. ALL RIGHTS RESERVED. SYN0716EN LAB160093_Synthetic_Diamond_Brochure_R14_EN.indd 1 12/13/16 12:12 PM Natural Diamonds Synthetic Diamonds Diamond Simulants Natural diamonds are a wonder of science, Following their extended time in residence in the Although their use for jewelry purposes is a somewhat Various materials have been used as imitations or as they occur only when atoms of carbon are mantle, some diamonds are brought to the earth’s recent occurrence, synthetic diamonds have been substitutes for diamonds since ancient times. These exposed to high pressures and temperatures surface by volcanic eruptions of kimberlite magma. produced for industrial applications since the 1950s. materials, often referred to as diamond simulants, about 100 miles (160 kilometers) below the earth’s Geologists believe that the diamonds are transported Unlike natural diamonds, synthetic diamonds are may grow naturally in the earth or artificially in surface in what geologists call the upper mantle. by the magma very quickly over the 100-mile distance grown in laboratories, over a very short period of a lab. Years ago, the colorless varieties of some Diamond crystals reside in these extreme mantle (in just a week or more), so that the diamonds are not time – likely just two or three weeks (or less). A colored stones (i.e., quartz) were used to simulate conditions for millions of years. The crystals physically changed in the process and transformed to longer growth period results in larger crystals; diamond. Today, the most common simulants are that grow under these conditions have a unique graphite. During this rapid upward journey, the diamond however, steady environmental conditions must be cubic zirconia (zirconium oxide, or CZ), and to a structure we associate with natural diamonds. crystal can, however, break along cleavage directions, maintained to ensure the formation of high-quality lesser extent, synthetic moissanite (silicon carbide). and undergo other changes that may affect, for crystals. Currently, the production of synthetic Because simulants differ completely from diamond, Natural diamond crystals sometimes incorporate solid diamonds in melee sizes is what is most encountered. example, its color. they display diagnostic properties by which they small inclusions of diamonds or other minerals into The drastically shorter growth period of synthetic can be recognized with standard gem testing their structure as they grow. While mineral inclusions diamonds results in features that are of diagnostic techniques, observations under magnification are often considered a negative clarity feature in a value in separating them from natural diamonds. and commercially available “diamond testers.” polished diamond, they are of tremendous value to Two artificial growth methods are used to create geoscientists. Natural diamonds provide a way for synthetic diamonds: HPHT and CVD. HPHT (high these mineral inclusions to be preserved and brought pressure/high temperature) synthesis, developed in to the earth’s surface where they can be scientifically the 1950s, uses high temperatures and pressures, a studied. Because certain inclusions contain radioactive molten metal flux and a diamond seed to initiate crystal elements that decay at a known rate, the minerals can formation. The result is a distinctive crystal shape which also be used to calculate the age of diamond formation. is a combination of octahedral and cube faces and a flat base. The HPHT process more closely mirrors the conditions of natural diamond formation than CVD. The CVD (chemical vapor deposition) method, which Volcanic chain A natural diamond is a gift from the earth. A cutter carefully examines the rough was mostly developed during the past decade, produces Mid-ocean ridge Subduction zone before polishing to a finished gem of optimal beauty. Courtesy: Aftergut N. & Zonen. Antwerp, Belgium diamonds through the use of low pressures and high temperatures Mobile belt in a vacuum chamber. A carbon- 140 km Graphited Diamond simulants, from top (left to right): Strontium titanate, synthetic spinel, Craton Diamon containing gas such as methane is synthetic rutile, yttrium aluminum garnet (YAG), zirconium oxide (CZ), zircon. UPPER MANTLE introduced into the chamber, and gas 410 km molecules break down there into the l Mantle keel with TRANSITION ZONE ithospheric diamonds constituent atoms. The carbon atoms 660 km “rain” down onto flat diamond seed LO plates, resulting in a square-shaped, WER MANTLE Mantle plum Rough colorless HPHT 900 km e tabular synthetic diamond crystal. synthetic crystals. Superdeep diamonds KimberlitKimberliteeBasalBasalt/Eclogitet/Eclogite LithosphericLithospheric mantle mantle ConvectingConvecting mantle mantle This block diagram depicts the basic relationship between a continental craton, its lithospheric mantle keel, and diamond stability regions in the keel and the convecting mantle. Under the right conditions of low oxidation, diamonds can form in the convecting mantle, the subducting slab, and in the majority of cases, in the mantle keel. Courtesy: Steven B. Shirey, modified from R. Tappert and M.C. Tappert, Diamonds in Nature: A Guide to Rough Diamonds (2011) Natural Diamond Synthetic Diamond Cubic Zirconia LAB160093_Synthetic_Diamond_Brochure_R14_EN.indd 2 12/13/16 12:12 PM.
Recommended publications
  • Simultaneous Diamond, White Sapphire & Moissanite
    SIMULTANEOUS DIAMOND, WHITE SAPPHIRE & MOISSANITE TESTER NEW ADVANCED EXCLUSIVE TECHNOLOGY RECOMMENDED by CHARLES & COLVARD CREATED MOISSANITE READ BEFORE USING The new moissanite that was introduced in late 2015 has changed. It can no longer be easily visually identified. It is now D-E-F “colorless”, with few inclusions. More importantly, standard diamond/moissanite testers will identify it as diamond since it is now only very slightly electrically conductive. The UltraTester 3+ uses new technology and is calibrated to identify this faint property. Be aware that body oil is also electrically conductive. Due to the tester’s enhanced sensitivity, dirty diamonds may test as moissanite. To avoid false/positive readings on dirty diamonds, ALWAYS CLEAN THE STONE on a cloth prior to testing. Periodically, also clean any accumulated body oil off of the probe tip by gently rubbing it on uncoated paper - SEE MANUAL. NEED HELP? Call GemOro at 800.527.0719 for immediate assistance. The GemOro UltraTester 3+ is the ultimate tester for diamond fraud protection that’s exclusively RECOMMENDED BY CHARLES & COLVARD, the manufacturer of created moissanite! The UltraTester 3+ features NEW ADVANCED EXCLUSIVE TECHNOLOGY capable of identifying the widest range of the electrically conductive moissanite material available, including the new super-low electrically conductive moissanite. OPERATING PROCEDURE & OWNERS MANUAL Congratulations on your purchase of the UltraTester 3+ from GemOro Superior GEMORO ULTRATESTER 3+ 2 Instruments, the most trusted name in gemological instrumentation for the jewelry industry. You’ve made a great choice. Built upon the foundation of the second generation and most popular tester to date, the UltraTester 3+ offers even more.
    [Show full text]
  • The Journal of Gemmology Editor: Dr R.R
    he Journa TGemmolog Volume 25 No. 8 October 1997 The Gemmological Association and Gem Testing Laboratory of Great Britain Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London Eel N SSU Tel: 0171 404 1134 Fax: 0171 404 8843 e-mail: [email protected] Website: www.gagtl.ac.uklgagtl President: Professor R.A. Howie Vice-Presidents: LM. Bruton, Af'. ram, D.C. Kent, R.K. Mitchell Honorary Fellows: R.A. Howie, R.T. Liddicoat Inr, K. Nassau Honorary Life Members: D.). Callaghan, LA. lobbins, H. Tillander Council of Management: C.R. Cavey, T.]. Davidson, N.W. Decks, R.R. Harding, I. Thomson, V.P. Watson Members' Council: Aj. Allnutt, P. Dwyer-Hickey, R. fuller, l. Greatwood. B. jackson, J. Kessler, j. Monnickendam, L. Music, l.B. Nelson, P.G. Read, R. Shepherd, C.H. VVinter Branch Chairmen: Midlands - C.M. Green, North West - I. Knight, Scottish - B. jackson Examiners: A.j. Allnutt, M.Sc., Ph.D., leA, S.M. Anderson, B.Se. (Hons), I-CA, L. Bartlett, 13.Se, .'vI.phil., I-G/\' DCi\, E.M. Bruton, FGA, DC/\, c.~. Cavey, FGA, S. Coelho, B.Se, I-G,\' DGt\, Prof. A.T. Collins, B.Sc, Ph.D, A.G. Good, FGA, f1GA, Cj.E. Halt B.Sc. (Hons), FGr\, G.M. Howe, FG,'\, oo-, G.H. jones, B.Se, PhD., FCA, M. Newton, B.Se, D.PhiL, H.L. Plumb, B.Sc., ICA, DCA, R.D. Ross, B.5e, I-GA, DGA, P..A.. Sadler, 13.5c., IGA, DCA, E. Stern, I'GA, DC/\, Prof. I.
    [Show full text]
  • Colourless Gemstones
    GEMS THE gem DeteCTIVE: COLOURLess gemstONes superseded in the 1970s by a man-made gemstone called cubic zirconia that is still the most popular and common diamond imitation in modern jewellery due to its low cost, high dispersion and good hardness (8.5 on Mohs scale). Another man-made gemstone called synthetic Moissanite was introduced as a diamond simulant in the late 1990s. Although TED A synthetic Moissanite tests positive on a FFILI A diamond tester, it is easily distinguished from diamond by a property called double refraction, detected using a 10x loupe. This property is also displayed by zircon, a natural CCREESH, O’NEILS O’NEILS CCREESH, gemstone with a sub-adamantine lustre. M N N A Complicating the process of identification are treatments that may affect the value of gemstones. For example, a laser may be used to drill down to a dark diamond inclusion and remove it using acid in a process called GE COURTESY OF BREND OF COURTESY GE laser drilling. Also common is fracture filling, ma I where a high refractive-index lead glass is used to fill surface-reaching fractures to make Sparkling, colourless gemstones may People love to assume that their great ALTHOUGH them less visible. Fortunately, both of these appear similar to the naked eye but they grandma’s solitaire engagement ring SYNTHETIC treatments are easily identified using a loupe can vary significantly in identity, rarity contained a natural diamond by virtue MOISSANITE or microscope. TESTS POSITIVE and value. Making such distinctions of its age but they should think again. Some off-coloured diamonds may be ON A DIamOND requires the detective skills of a qualified Synthetically-produced sapphire, spinel and TESTER, IT CAN BE whitened using High Pressure High gemmologist.
    [Show full text]
  • Gemstones by Donald W
    GEMSTONES By Donald W. olson Domestic survey data and tables were prepared by Nicholas A. Muniz, statistical assistant, and the world production table was prepared by Glenn J. Wallace, international data coordinator. In this report, the terms “gem” and “gemstone” mean any gemstones and on the cutting and polishing of large diamond mineral or organic material (such as amber, pearl, petrified wood, stones. Industry employment is estimated to range from 1,000 to and shell) used for personal adornment, display, or object of art ,500 workers (U.S. International Trade Commission, 1997, p. 1). because it possesses beauty, durability, and rarity. Of more than Most natural gemstone producers in the United states 4,000 mineral species, only about 100 possess all these attributes and are small businesses that are widely dispersed and operate are considered to be gemstones. Silicates other than quartz are the independently. the small producers probably have an average largest group of gemstones; oxides and quartz are the second largest of less than three employees, including those who only work (table 1). Gemstones are subdivided into diamond and colored part time. the number of gemstone mines operating from gemstones, which in this report designates all natural nondiamond year to year fluctuates because the uncertainty associated with gems. In addition, laboratory-created gemstones, cultured pearls, the discovery and marketing of gem-quality minerals makes and gemstone simulants are discussed but are treated separately it difficult to obtain financing for developing and sustaining from natural gemstones (table 2). Trade data in this report are economically viable deposits (U.S.
    [Show full text]
  • Identifying Diamonds Diamond Is One of the Most Important Gemstones Traded in the World Today
    GEMMOLOGY Identifying Diamonds Diamond is one of the most important gemstones traded in the world today. Diamond has all properties in the superlative state- best luster, highest hardness, highest thermal conductivity among gems and these properties help in identification and form the basis for some of the tips to check whether the white stone is a diamond. t is said that Alexander the stone then do so only with a stone case of simulants, the line will Great found a valley full of both holder or tweezer. Never move appear partially or complete. This Idiamonds and poisonous snakes. your fingers through the diamonds, test can be easily carried out on No one could work out how to you would never know how many unset stones; but care must be retrieve the jewels until Alexander diamonds would get stuck to your taken when they are mounted. had the idea of throwing down fingers and fall out. Confusion is possible with raw meat, to which the diamonds old cut diamonds, in which full attached. When eagles flew down Visual Methods advantage of the low critical angle for the meat, Alexander's men just was not taken in cutting. Here, the had to follow them to their nests. It Tilt Test line may appear unnaturally clear or sounds like fantasy but diamonds The high Refractive Index (RI) of transparent for diamonds. The large are attracted to fat, and the story Diamond makes possible a simple culet and the facet edges will be reminded people how to tell real test to distinguish it quickly from immediately apparent to the naked diamonds from fakes.
    [Show full text]
  • Diamond Terminology Guideline
    DIAMOND TERMINOLOGY GUIDELINE INTRODUCTION AND REFERENCE Nine of the leading diamond industry organisations (AWDC, CIBJO, DPA, GJEPC, IDI, IDMA, USJC, WDC and WFDB) have developed the present guideline to encourage full, fair and effective use of a clear and accessible terminology for diamonds, synthetics diamonds and imitations of diamonds by all sector bodies, organisations and traders. This Diamond Terminology Guideline serves as a reference document for the diamond and jewellery trade when referring to diamonds and synthetic diamonds. It is built on two internationally accepted standards: the ISO 18323 Standard (“Jewellery – Consumer confidence in the diamond industry”) and the CIBJO Diamond Blue Book. DEFINITIONS Ø A diamond is a mineral created by nature; a “diamond” always means a natural diamond. Ø A synthetic diamond is an artificial product that has essentially the same physical characteristics as a diamond. Ø An imitation diamond, also named a diamond simulant, is an artificial product that imitates the appearance of diamonds without having their chemical composition, physical properties or structure. Ø A gemstone is a mineral of natural origin that is used in jewellery for reasons of combined beauty, rareness and intrinsic value. TERMINOLOGY Ø When referring to synthetic diamonds: - Use one of the following authorised qualifiers when referring to synthetic diamonds: “synthetic”, “laboratory-grown” or “laboratory-created”. - Do not use abbreviations such as “lab-grown” and “lab-created”. - Do not use the following terms: “cultured diamonds” and “cultivated diamonds” as “cultured” and “cultivated” refer exclusively to organic/biogenic products. - Do not use the following terms: “real”, “genuine”, “precious”, “authentic” and “natural” as those apply exclusively to natural minerals and gemstones.
    [Show full text]
  • Diamond Terminology Guideline Serves As a Word “Diamond” Without a Qualifier When Referring to Reference Document for the Diamond and Jewellery Trade a Diamond
    Diamond Terminology Terminology • When referring to synthetic diamonds: Guideline - Use one of the following authorised qualifiers when referring to synthetic diamonds: “synthetic”, Introduction & Reference “laboratory-grown” or “laboratory-created”. - Do not use abbreviations such as “lab-grown” and National Association of Jewellers (NAJ) together with nine “lab-created”. of the leading diamond industry organisations (AWDC, - Do not use the following terms: “cultured CIBJO, GJEPC, IDI, IDMA, NDC, RJC, WDC and WFDB) diamonds” and “cultivated diamonds” as “cultured” endorses the present guideline to encourage full, fair and “cultivated” refer exclusively to organic/biogenic and effective use of a clear and accessible terminology products. for diamonds, synthetics diamonds and imitations - Do not use the following terms: “real”, “genuine”, of diamonds by all sector bodies, organisations and “precious”, “authentic” and “natural” as those apply traders. exclusively to natural minerals and gemstones. • A diamond is natural by definition. Therefore, use the This Diamond Terminology Guideline serves as a word “diamond” without a qualifier when referring to reference document for the diamond and jewellery trade a diamond. If differentiation from synthetic diamonds when referring to diamonds and synthetic diamonds. It is is required, use the term “natural diamonds” as term built on two internationally accepted standards: the ISO of equivalent meaning. 18323 Standard (“Jewellery – Consumer confidence in • Do not use the following confusing expressions: the diamond industry”) and the CIBJO Diamond Blue “natural treated diamonds” and “treated natural Book. diamonds”. Instead, simply use “treated diamonds”. Definitions • A diamond is a mineral created by nature; a “diamond” always means a natural diamond. • A synthetic diamond is an artificial product that has essentially the same physical characteristics as a diamond.
    [Show full text]
  • Gemmological Association and Gem Testing Laboratory of Great Britain
    Gemmology Volume 26 No. 7 The Gemmological Association and Gem Testing Laboratory of GreatvBritain Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London EC1N 8TN Tel: 020 7404 3334 Fax: 020 7404 8843 e-mail: [email protected] Website: www.gagtl.ac.uk/gagtl President: Professor R.A. Howie Vice-Presidents: E.M. Bruton, A.E. Farn, D.G. Kent, R.K. Mitchell Honorary Fellows: Chen Zhonghui, R.A. Howie, R.T. Liddicoat Jnr, K. Nassau Honorary Life Members: H. Bank, DJ. Callaghan, E.A. Jobbins, H. Tillander Council of Management: T.J. Davidson, N.W. Deeks, R.R. Harding, I. Mercer, J. Monnickendam, MJ. O'Donoghue, E. Stern, I. Thomson, V.P. Watson Members' Council: A.J. Allnutt, P. Dwyer-Hickey, S.A. Everitt, A.G. Good, J. Greatwood, B. Jackson, L. Music, J.B. Nelson, P.G. Read, R. Shepherd, PJ. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West -1. Knight, Scottish - B. Jackson Examiners: A.J. Allnutt, M.Sc, Ph.D., FGA, L. Bartlett, B.Sc., M.Phil., FGA, DGA, E.M. Bruton, FGA, DGA, S. Coelho, B.Sc, FGA, DGA, Prof. A.T. Collins, B.Sc, Ph.D, A.G. Good, FGA, DGA, J. Greatwood, FGA, G.M. Howe, FGA, DGA, B. Jackson, FGA, DGA, G.H. Jones, B.Sc, Ph.D., FGA, M. Newton, B.Sc, D.Philv CJ.E. Oldershaw, B.Sc. (Hons), FGA, H.L. Plumb, B.Sc, FGA, DGA, R.D. Ross, B.Sc, FGA, DGA, PA. Sadler, B,Sc, FGA, DGA, E. Stern, FGA, DGA, S.M.
    [Show full text]
  • (12) United States Patent (10) Patent No.: US 9,055,792 B2 Malinowski Et Al
    US009055792B2 (12) United States Patent (10) Patent No.: US 9,055,792 B2 Malinowski et al. (45) Date of Patent: Jun. 16, 2015 (54) SAPPHRE COATED GEMSTONE (2015.01); Y10T 428/261 (2015.01); Y10T 428/265 (2015.01); C23C 14/221 (2013.01); (75) Inventors: Jack Malinowski, Austin, TX (US); C23C 14/081 (2013.01); C23C 14/3442 Gary Lacourt, Franklin, WI (US); (2013.01); A44C 27/007 (2013.01) Frank Calcagni, Austin, TX (US) (58) Field of Classification Search None (73) Assignee: Lautrec Corporation, Franklin, WI See application file for complete search history. (US) (56) References Cited (*) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S. PATENT DOCUMENTS U.S.C. 154(b) by 382 days. 3,539,379 A * 1 1/1970 Mayer ...................... 427/25519 5,573,684. A * 1 1/1996 Winston et al. .......... 219,121.85 (21) Appl. No.: 13/577,068 6,025,060 A * 2/2000 Meissner ...................... 428, 220 2005/0274144 Al 12/2005 Goughnour (22) PCT Fled: Feb. 4, 2011 2007. O157667 A1* 7, 2007 MalteZOS et al. .................. 63,32 2008/0282733 A1 11/2008 Tollwani (86) PCT NO.: PCT/US2011/023771 2009/0246370 A1* 10/2009 Gupta et al. ............... 427,248.1 2010/0068503 A1* 3/2010 Neogi et al. .................. 428,323 S371 (c)(1), (2), (4) Date: Mar. 19, 2013 FOREIGN PATENT DOCUMENTS (87) PCT Pub. No.: WO2O11AO97498 GB 1491361. A * 11, 1977 PCT Pub. Date: Aug. 11, 2011 OTHER PUBLICATIONS (65) Prior Publication Data O'Donoghue, GEMS, 2006, pp. 524-526 and 782-791.* US 2013/0239614 A1 Sep.
    [Show full text]
  • The Separation of Natural from Synthetic Colorless Sapphire
    THE SEPARATION OF NATURAL FROM SYNTHETIC COLORLESS SAPPHIRE By Shane Elen and Emmanuel Fritsch Greater amounts of colorless sapphire—promot- undreds of millions of carats of colorless syn- ed primarily as diamond substitutes, but also as thetic sapphire are manufactured annually (all natural gemstones—have been seen in the gem growth techniques combined), according to B. market during the past decade. In the absence of MudryH of Djevahirdjian in Monthey, Switzerland, a leading inclusions or readily identifiable growth struc- producer of Verneuil synthetics (pers. comm., 1997). He esti- tures, natural colorless sapphires can be separat- mates that about 5%–10% of this production (50–100 mil- ed from their synthetic counterparts by their lion carats) is used by the jewelry industry. Distinguishing trace-element composition and short-wave ultraviolet (SWUV) transparency. Energy-disper- natural from synthetic colorless sapphire can often, but not sive X-ray fluorescence (EDXRF) analysis shows always, be accomplished by standard gemological testing higher concentrations of trace elements (i.e., Fe, (see below). However, this distinction is time consuming for Ti, Ca, and Ga) in natural sapphires. These large parcels, and it is difficult to impossible for melee-size impurities cause a reduction in SWUV trans- stones. parency that can be detected by UV-visible spec- As first described more than 50 years ago (Wild and trophotometry (i.e., a total absorption in the UV Biegel, 1947), natural colorless corundum can be separated region below 280–300 nm, which is not seen in from flame-fusion synthetic colorless corundum (only their synthetic counterparts). This article Verneuil material was being produced at that time) by a dif- describes a SWUV transparency tester that can ference in transparency to short-wave ultraviolet (SWUV) rapidly identify parcels of colorless sapphires.
    [Show full text]
  • Spring 1981 Gems & Gemology
    -, I.. - VOLUME XVll SPRING 1981 \ .: I SPRING 1981 Volume 17 Number I TABLE OF CONTENTS EDITORIAL 1 An Introduction to the New Gems & Gemology Richard T. Liddicoat, /r. FEATURE 2 Zabargad: The Ancient Peridot Island in the Red Sea ARTICLES Edward Gu belin 9 Cubic Zirconia: An Update Kurt Nassau 20 A Simple Approach to Detecting Diamond Simulants !ill Hobbs NOTES AND 34 The Hidden Beauty of Amber: New Light on an Old Subject NEW yohn I. Koivr~la TECHNIQUES 37 Artificially Induced Color in Amethyst-Citrine Quartz Kurt Nassau REGULAR 40 Gem Trade Lab Notes FEATURES 47 Gemological Abstracts 56 Gem News 59 Book Reviews ABOUT THE COVER: The elemen~soj gemology ore summed up in th~sclossic pose: microscope, books, faceted stone (in this cnse, o 32.21 ct, oqriamorine), and nrriurol crystal (here, on oquamorine jrom Ajghonistan, courlesy of the Los Angeles County Museum of Noturol History, Los Angeles, CA). Cover design by Peter lohns~on,photogrophy by Michoel Havstad. Composition for Gems & Gemology is done by Printed Poge Graphics, Fullerton, CA. The color sepnrotions ore done by Effective Grophics, Compton, CA. Printing is by Woverly Press, Eoston, MD. " 1981 Gemological Institute of America. All rights reserved. EDITORIAL Editor-in-Chief Managing Editor Editor, Geni Trade Lab Notes STAFF Richard T. Lidtlicoat, jr. Alicc S. Keller Chuck Fryer Associate Editor 1660 Stcwart St. Editor, Geniologiwl Abstracts Peter C. Keller Santn Monica, CA 90404 Ilona Pvl. Dirlnrn Telephone: (213) 829-299 1 Associate Editor Editor, Book Reviews D. Vincent manso on Subscriptions Manager John I. I<oivula Margaret Orozco Contributing Editor Editor, Gem News John I.
    [Show full text]
  • The Essential Engagement Ring Handbook – Lisa Krikawa
    The Essential Engagement Ring Handbook by Lisa Krikawa 1 THE ESSENTIAL ENGAGEMENT RING HANDBOOK Make Knowledgeable Choices and Avoid Expensive Mistakes When Investing in the Most Significant Jewelry Purchase of Your Life By Lisa Krikawa www.krikawa.com The Essential Engagement Ring Handbook by Lisa Krikawa 2 Copyright © 2016 by Lisa R. Krikawa All rights reserved. This book or parts thereof may not be reproduced in any form, stored in any retrieval system, or transmitted in any form by any means—electronic, mechanical, photocopy, recording, or otherwise—without prior written permission of the publisher, except as provided by United States of America copyright law. For permission requests, write to the publisher, at “Attention: Permissions Coordinator,” at the address below. Created in the United States of America Visit the author’s website at www.krikawa.com. First Edition This book and the content provided herein are simply for educational purposes. Every effort has been made to ensure that the content provided in this book is accurate and helpful for our readers at publishing time. However, this is not an exhaustive treatment of the subjects. No liability is assumed for losses or damages due to the information provided. You are responsible for your own choices, actions, and results. Lisa Krikawa Krikawa Jewelry Designs 21 E. Congress St. Tucson, AZ 85701 www.krikawa.com The Essential Engagement Ring Handbook by Lisa Krikawa 3 This book is dedicated to PSI Seminars, PLD Team #57 To the Owner, Trainer, Coaches and Players, “Fly Like Eagles!” www.krikawa.com The Essential Engagement Ring Handbook by Lisa Krikawa 4 Table of Contents Preface ................................................................................................................................
    [Show full text]