| Eur. J. Mineral. 2002, 14, 1109–1118 Agate: a study of ageing TERRY MOXON 55 Common Lane, Auckley, Doncaster...measured using X-ray powder diffraction. A plot of agate crystallite size vs log age of host rock shows a...increase in density. A high correlation between agate crystallite size and age of host rock shows that...determination of crystallite size in wall-lining agate allows either an estimation of the approximate age...rock or an identification of a known agate region. Key-words: agate, dating, silica, X-ray, genesis, density |
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| images Front cover top Agate from Germany; bottom Agate from Scotland. Back cover Agate from Germany. Title...Title page Agate from Russian Arctic coast. Distribution NBN International Estover Road Devon PL6 7PY ... Contents Introduction Names of agates What is an agate? Properties of agates Sources of agates Europe...different geological environments. Since the mid-1900s, agate collecting has become very popular in Europe, North...America and the Middle East. There are thousands of _agate_-producing areas on Earth, and in the following pages |
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Pabian, Roger, Jackson, Brian, Tandy, Peter, Cromartie, John (2006) Agates - Treasures of the Earth. Natural History Museum, London. |
Book |
| Images Front cover top Agate from Germany: bottom Agate from Scotland. Back cover Agate from Germany. Title...Title page Agate from Russian Arctic coast. Distribution NBN International Estover Road Devon PL6 ?PY UK...Introduction 4 Names of agates 6 What is an agate? 10 Properties of agates 44 Sources of agates...geological environments. Si nce the mid-1900s, agate collecting has become very popular in Europe, North...America and the M iddle East. There are thousands of _agate_-producing areas on Earth, and in the following pages |
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Moxon, Terry, Rí os, Susana (2004) Moganite and water content as a function of age in agate: an XRD and thermogravimetric study. European Journal of Mineralogy, 16 (2) 269-278 doi:10.1127/0935-1221/2004/0016-0269 |
Journal (article/letter/editorial) |
| Moganite and water content as a function of age in agate: an XRD and thermogravimetric study TERRY MOXON*...crystallites. The maximum content of moganite found in agate was 14 % but after ~ 410 Ma it is only present in...moganite transformation, the internal water in agate has been found to be constant at ~ 0.4 %. The change...in the crystallites from 8 regions suggests that agate genesis would be typically penecontemporaneous with...solutions are the source of the silica in all cases of agate genesis in an igneous environment. With minimal |
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Bonewitz, Ronald Louis (2013) Gems. Dorling Kindersley Limited DK, London. |
Book |
| into new rocks. pyramidal , crystal mica schist agate lining garnet crystal Garnet in schist This almandine...Staining or dyeing is very widespread. Slices of agate are routinely dyed with vivid colors such as blue...the Indus Valley Civilization, this necklace of agate, chalcedony, and jasper beads is probably from Mohenjodaro...3000sce, “magical” amulets were being cut from agate, carnelian, turquoise, and lapis lazuli in Egypt...antique turquoise ornament from Persia (present-day Iran) is an example of the highest lapidary skill. Cabochon |
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Polk, Patti (2010) Collecting Rocks, Gems and Minerals: Identification, Values and Lapidary Uses (1st ed.) Krause Publications. |
Book (edition) |
| holding a shiny crystal or an expertly polished agate in their hands. It is even more gratifying to actually...The search for a lustrous crystal or a colorful agate is truly a worthwhile and satisfying recreational...lonely journeys to find that ever-elusive next agate, jasper, or mineral specimen that will be the most...within the field of the lapidary arts. A rough agate as found in the field weighing about three pounds...pounds. A silver ring set with a freeform agate cabochon hand collected, cut, and polished by the author |
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Hall, Cally (1994) Gemstones - Eyewitness Handbooks - The Visual Guide to more than 130 Gemstone Varieties. Dorling Kindersley Ltd., London. |
Book |
| Fairly soft, goodfire Chatoyant Quartz 86 Moss Agate 89 Fibrous structure mosslike pattern Translucent...luster 1 15 Sometimes Green MiCROCLiNE 123 Agate 88 Distinctive blue- Translucent, green color...pleochroic I COLOR KEY Other Gems Apatite 79 Agate (stained) 88 Ho\\TiTE (stained) 128 Cafs-eyes,...heat, soft Iridescent Gemstoxes Opal 134 Fire Agate 87 Iridescent colors, Iridescence resembles may...Hardness gjij^^^ ^^^^^^^ Fire Agate (Chalcedony) iridescence Fire agate belongs to the chalcedony family |
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(1968) The Journal of Gemmology Vol. 11 (1) Gem-A |
Journal (issue) |
| poor-ish, highly coloured illustration of fortification-agate (also 1959). There are two illustrations... Ifield Rectory, Kent Zarobabely, Aron, Tehran, Iran Fraley, Robert J., Carolina, U.S.A. Saleh, Zurairul-Ameen...MOONSTONES GARNETS (rough & cut) INDIA STAR RUBIES AGATE NECKLACES .~ . , ~ m ~ > C\ m Z .... '" |
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Götze, Jens, Möckel, Robert, Pan, Yuanming (2020) Mineralogy, Geochemistry and Genesis of Agate—A Review. Minerals, 10 (11) 1037 doi:10.3390/min10111037 |
Journal (article/letter/editorial) |
| Review Mineralogy, Geochemistry and Genesis of _Agate_—A Review Jens Götze 1, *, Robert Möckel 2 and Yuanming...20 November 2020 Abstract: _Agate_—a spectacular form of SiO2 and a famous gemstone—is...interstitial molecular H2 O and silanol groups. Most agate occurrences worldwide are related to SiO2 -rich...rocks. It is assumed that the supply of silica for agate formation is often associated with late- or post-volcanic...studies point to a range between 20 and 230 ◦ C for agate formation temperatures. The accumulation and condensation |
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O'Donoghue, Michael (1987) Quartz. Butterworths. |
Book |
| all rock types and in most countries. CHALCEDONY Agate (light to dark colours in concentric bands, translucent)...translucent), fire agate (dark agate with play of colour similar to that in opal, opaque), moss agate (pale yellow...the categories Silex or Kieselstein (including agate, flint opal), Petrosilex or Halleflinta (for jasper...a species of cherry with a reddish fruit. Moss agate is characterized by dendritic growths resembling...for this material. Sagenitic agate contains acicular inclusions. Agate proper is a variety of chalcedony |
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Thoresen, Lisbet (ed.), Overlin, Stuart (ed.) (2021) Agate and Chalcedony. 17th Sinkankas Symposium, 17. Pala International, Inc. |
Conference Proceedings (Volume) |
| SINKANKAS SYMPOSIUM AGATE and CHALCEDONY SEVENTEENTH ANNUAL SINKANKAS SYMPOSIUM AGATE and CHALCEDONY Co-sponsored...Gemological Institute of America FRONT COVER Iris Agate (90.2 x 86.1 mm), from Chihuahua Mexico. Photo by...Title Seventeenth Annual Sinkankas Symposium – Agate and Chalcedony Editors Lisbet Thoresen and Stuart...DPI Direct, Poway, California BACK COVER Laguna Agate (162.2 mm), detail, from Ojo Laguna, Chihuahua,...978-0-9915320-5-6 SEVENTEENTH ANNUAL SINKANKAS SYMPOSIUM AGATE and CHALCEDONY CONTENTS Dedication and Acknowledgments |
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Shipley, Robert M. (1974) Dictionary of Gems and Gemology (6th ed.) Gemological Institute of America, Los Angeles. |
Book (edition) |
| from India, ground for use as Agate. achates. Ancient name for agate. Free achromatic from color;...green tourmaline. See African emerald. Moss agate. agate (ageg’-it). One of the many varieties of chalcedony...translucent form with dendritic inclusions (moss agate). It is found in virtually all colors, usually of...translucent to semitransparent. Most gray-banded agate is African emerald. Emerald from the Transvaal...Trade dyed to onyx, moss agate and improve its color. See agate. jasper. Mixture of jasper chalcedony |
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Desautels, Paul E. (1971) The Gem Kingdom. Random House, New York. |
Book |
| Taurus for Asmodel, carbuncle for Ambriel, emerald Agate Gemini for Muriel, sapphire for Herchel, diamond...Emerald Cancer Humatiel, jacinth for Zuriel, agate for Barbiel, Leo amethyst for Adnachiel, beryl...April July amethyst to ward off intoxication, agate for Garnet or malachite as protection against...Joseph 8 Shebo achates amethystos achates agate agate Benjamin 9 Ahlamah amethystos achates ...dyed and imitation gem materials, including dyed agate, synthetic quartz, imitation pearls, glass, and |
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Schumann, Walter (1999) Gemstones of the World (2nd ed.) Sterling Publishing Co., Inc., New York. |
Book (edition) |
| Properties of Gemstones Cutting and Polishing Agate 60 Hardness 19 Cutting and Polishing Colored Stones...Chrysoprase 128 Heliotrope 128 Dendritic Agate 130 Moss Agate 130 Agate 132 Jasper 146 Fossilized Wood 148...term colored stones all precious stones except agate and diamond. Colored Precious Stone (also for ...for its green color), their place of discovery ("agate" for a river in Sicily), or mysterious powers ("amethyst"...Staurolite Kornerupine Titanite Pyrope Senarmontite Agate Amethyst Lithiophilite Tremolite Manganotanitalite |
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(2016) Jewel - A Celebration of Earth's Treasures. Dorling Kindersley Limited, London. |
Book |
| statuette Chalcedony Frederick the Great’s snuffbox Agate Onyx 106 107 108 110 112 114 116 117 118 119 120...sometimes penetrate chalcedony to form dendritic agate. Acicular crystal form Dendritic crystal form ...AMETHYST CHRYSOBERYL APATITE RUBY CHALCEDONY AGATE AMBER LAZURITE COPAL Optical variations Each...Fluorite Sapphire Great Britain Sunstone Topaz Agate Tourmaline Aventurine Turquoise Quartz USA...Guatemala Sapphire Spinel Mexico Tourmaline Agate Moonstone Quartz Topaz Turquoise 65% Nigeria |
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Arem, Joel (1975) Gems and Jewelry. The Ridge Press, New York. |
Book |
| quartz, and the colored gem varieties are called agate and jasper. The basic crypto¬ crystalline matrix...common and least expensive of all gem materials. Agate was known to primitive man, and acquired a cloak...not the same as lapis lazuli (see pages 103-104). Agate is chalcedony in which the coloration takes the...inclusions. Fortification agate contains straight or concentric bands, while moss agate displays colored...holders, bookends, and boxes. Huge quan¬ tities of agate and jasper are tumble-polished for use in inexpensive |
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Pearl, Richard M. (1964) Gems, Minerals, Crystals and Ores - The Collector's Encyclopedia. The Odyssey Press, New York. |
Book |
| colored gems offer a much wider range of interest; agate, which is the most generally used of all the gems...opal) or the most attractive pattern (as in an agate). If the mineral is fibrous, the fibers should be... OXIDES Agate. The rich coloring and the distinctive and complete pattern of this Lake Superior agate from...side represents the original base of the agate. 41 Moss agate. So named for the branching pattern of...inclusions. From Oregon. Bull's-eye agate. The name of this agate from Winona, Minnesota, is most appropriate |
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Pearl, Richard M. (1964) Gems, Minerals, Crystals and Ores - The Collector's Encyclopedia. The Odyssey Press, New York. |
Book |
| colored gems offer a much wider range of interest; agate, which is the most generally used of all the gems...opal) or the most attractive pattern (as in an agate). If the mineral is fibrous, the fibers should be... OXIDES Agate. The rich coloring and the distinctive and complete pattern of this Lake Superior agate from...side represents the original base of the agate. 41 Moss agate. So named for the branch¬ ing pattern of...inclusions. From Oregon. Bull’s-eye agate. The name of this agate from Winona, Minnesota, is most appropriate |
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Pearl, Richard M. (1964) Gems, Minerals, Crystals and Ores - The Collector's Encyclopedia. The Odyssey Press, New York. |
Book |
| Actually, gems offer a much wider range of interest; agate, which is the most generally used of all the gems...color (as in most attractive pattern (as in an agate). If the mineral is fibrous, the fibers should...OXIDES Agate. The rich coloring and the distinctive and complete pattern of this Lake Superior agate from...side represents the original base of the agate. 41 Moss agate. So named for the branch- ing pattern...inclusions. From Oregon. i Bull’s-eye agate. The name of this agate from Winona, Minnesota, is most appropriate |
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Schumann, Walter (2006) Gemstones of the World (3rd ed.) Sterling Publishing Co., Inc., New York. |
Book (edition) |
| Production of Gemstones oS 70 Cutting and Polishing Agate 71 Cutting and Polishing Colored Stones _ Cabochon...Rhodochrosite Dendritic Agate 146 184 Rhodonite Pyrope 120 Kimandite 120 Moss Agate 146 Agate 148 : 186 Turquoise...for its green color), their place of discovery (“_agate_” for a river in Sicily), or mysterious powers (“amethyst”...Thaumasite Vanadinite Wurizite Zincite trigonal Agate Achroite Amethyst Amethyst Quartz Ametrine Ankerite...Chrysoprase Citrine Cinnabar Corundum Davidite Dendritic Agate Dioptase Dolomite Dravite Elbaite Eudialyte Gaspeite |
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Arem, Joel E. (1977) Color Encyclopedia of Gemstones (1st ed.) Van Nostrand Reinhold Company, Inc. |
Book (edition) |
| Formula: Approximately See: Feldspar. AGALMATOLITE AGATE See: Pyrophyllite. ALBITE See: Calcite, Gypsum...Related Czechoslovakia and minerals are Mesanki, Iran. found at Beloves, Stone Sizes: Cabochons could...(Ceylon, Brown); 6.7 (star, Brazil). Crown Jewels of Iran: Catseye, 147.7 (chartreuse color, Ceylon); 25 (catseye...Austria). DG; 7.30 (clinozoisite, brownish, Iran); 6.90 (epidote, brown) PC: 220 (blue, tanzanite...FERROHYPERSTHENE FERROSALITE FERROSILITE FIBROLITE FIRE AGATE FLINT See: Enstatite. See: Manganotantalite. See: |
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(1995) The Minerals and Gemstones Collection [Collated] : Gemstones. Treasures of the Earth. Orbis Publishing Ltd. |
Journal (issue) |
| PRECIOUS GEMSTONES, AGATE CAN C) BE USED AS A POLISHER IN INDUSTRY z The colour of agate is highly variable...combinations of all these colours. m VARIETIES OF AGATE I Agate is an impure form of chalcedony. Chalcedony...that forms in micro- • scopically small crystals. Agate is distinguished from chalcedony by its characteristic...gemstone. These bands are not usually visible when the agate specimens are first removed from the ground (many...in form. The best of these patterns can make the agate extremely valuable as a decorative gemstone. There |
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(1966) Edelsteine [Precious Stones]. Verband der Edelstein- und Diamantindustrie e. V. . |
Book |
| from East lndia and late r, e\·cn more important, Agate from ßrazil were introduce.d into this area . The...Gcrman natural scicntist, Dr. Schellow, reporteAgate d cposits in Southcrn Brazil and neighbouring Urugua...rom prcvious cxpcricncc what could be dune with Agate. The first shipmcnt of 1\gate camc to Gcrm:iny in...and forms of the cut: 1. Agate cutting: Cabochon Cut Raw materi a l: Agate, Rhodod1rosite, Rh od onite...n und zum Zierat der G emächer r; brau t w r n . iran teilte sie au n eh dt:r Durchsichtigl-eit ein ·n: |
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(2016) Gem. The Definitive Visual Guide. Penguin Random House, London. |
Book |
| statuette Chalcedony Frederick the Great’s snuffbox Agate Onyx 106 107 108 110 112 114 116 117 118 119 120...sometimes penetrate chalcedony to form dendritic agate. Acicular crystal form Dendritic crystal form ...AMETHYST CHRYSOBERYL APATITE RUBY CHALCEDONY AGATE AMBER LAZURITE COPAL Optical variations Each...Fluorite Sapphire Great Britain Sunstone Topaz Agate Tourmaline Aventurine Turquoise Quartz US ...Guatemala Sapphire Spinel Mexico Tourmaline Agate Moonstone Quartz Topaz Turquoise 65% Nigeria |
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Arem, Joel E. (1977) Color Encyclopedia of Gemstones (1st ed.) Van Nostrand Reinhold Company, Inc. |
Book (edition) |
| ADULARIA AMBER See: Feldspar. AGALMATOLITE AGATE ALBITE See: Pyrophyllite. See: Calcite, Gypsum...re found at Belo,•es. Czechoslovakia and Mesanki, Iran. Stone Sizes: Cabochons could be cut to almost any...(Ceylon, Brown); 6. 7 (star, Brazil). Crown Jewels of Iran: Catseye, 147.7 (chartreuse color, Ceylon); 25 (catseye...brown, Austria). DG: 7.30 (chnozoisite, brownish, Iran); 6.90 (epidote, bro~n) PC: 220 (blue, tanzanite...MORGANITE MORION See: Beryl. See: Quartz. MOSS AGATE MUKHINITE See: Quartz. See: Epidote. N NAMBULITE |
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