 | | Journal (article/letter/editorial) | | 94720-4767, USA Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, CA 94709, USA Received 31 May...Laboratory, 7000 East Avenue, Livermore, CA 94550, USA. E-mail addresses: cassata2@llnl.gov (W.S. Cassata)...binocular microscope and irradiated for 50–200 h at the Oregon State University TRIGA reactor in the Cadmium-Lined...oligoclase 400 50 andesine Huttenlocher 70 labradorite 90 P1 200 An bytownite anorthite Fig. 1...from a pegmatite in Benson Mines near Star Lake, New York, USA (Foland, 1974). Benson Mines orthoclase was |  | | Journal (issue) | | and H . Stuart Smith Sunstone Labradorite from the Ponderosa Mine, Oregon Christopher L. Johnston, Mickey...largest producer of diamonds in 1990, t h e Argyle mine in Western Australia (36 million carats), fine gem-quality...et al., 1991). If we consider only the Kimberley mine ("Big Hole") as an example, and take into account...calculating the volume of rock removed from the Kimberley mine (the "Big Hole") in Kimberley, South Africa, the...Knowles 1 n 1985, the Oregon legislature named the gem variety of labradorite called sunstone as the |  | | Journal (issue) | | Patterns in Opal Agate from Morocco Field Report on Oregon Sunstone Fall 2013 VOLUME 49, No. 3 EDITORIAL...pg. 162 FIELD REPORT 162 Three Occurrences of Oregon Sunstone Duncan Pay, Robert Weldon, Shane McClure...Chronicles a visit to the high desert of eastern Oregon to examine commercial sources of this natural copper-bearing...Mouawad Campus 5345 Armada Drive Carlsbad, CA 92008 USA © 2013 Gemological Institute of America All rights...from a practical indication of heat treatment to Oregon sunstone to our lead article on the Museum of London’s |  | | Journal (issue) | | considered as a definite indication. Absorption-spectrum Viewed through the normal gemmological absorptionspectroscope...quite different: at the short-wave end of the spectrum the absorption-curve shows a marked transmission...transmission maxima in the near ultraviolet region of the spectrum. The transmission ends at 210 nm and 270 nm respectively...demonstrated, on the basis of a study of its infrared spectrum, that the structure is better represented by the...ruby-red to co pale brownish-orange. The absorption spectrum shows faint chromium lines. Between crossed polars |  | | Journal (article/letter/editorial) | | Institute of Technology, Pasadena, California 91125, USA Abstract. Ferrous and ferric iron concentrations...Institution of Washington, Washington D.C. 20008, USA Previous optical and EPR spectroscopic studies of...(1972) optical spectra of yellow labradorite from Lake County, Oregon, suggest that plagioclase accommodates...because of structural state. Early EPR studies of labradorite, bytownite, and anorthite indicate that trivalent...(1978) resolved this discrepancy by proving that labradorite and bytownite have two different sites with apparent |  | | Book (volume) | | Lachman. Photo from Van Lachman. Opposite page: Oregon sunstone beads, earrings, pendant and loose sunstones...Publications P.O. Box 13384 Los Angeles, CA 90013-0384 USA (Inquiries should be accompanied by a self-addressed...Rhodochrosite earring and photo from Timeless Gems Oregon Sunstone carving and photo from Daylan Hargrave...Metaphysical Properties of Sunstone 110 Production of Oregon Sunstone 110 Sunstone Price Factors 112 11. Moonstone...Other Feldspars 127 Labradorite (Labradorescent Variety) 127 Yellow or Golden Labradorite 130 Andesine 133 |  | | Journal (issue) | | 401 FEATURE ARTICLES 400 A Canary in the Ruby Mine: Low-Temperature Heat Treatment Experiments on Burmese...of Two Copper-Diffused Plagioclase Feldspars: Labradorite and Andesine Qingchao Zhou, Chengsi Wang, and...Mouawad Campus 5345 Armada Drive Carlsbad, CA 92008 USA © 2022 Gemological Institute of America All rights...decade. Conducting experiments on both colorless labradorite and light yellow andesine feldspar to modify...2022 399 FEATURE ARTICLES A CANARY IN THE RUBY MINE: LOW-TEMPERATURE HEAT TREATMENT EXPERIMENTS ON BURMESE |  | | Journal (article/letter/editorial) | | 94720-4767, USA 2. Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, CA 94709, USA 3. Chemical... 7000 East Avenue (L-231), Livermore, CA 94550, USA * Corresponding author. Email addresses: mtremblay@berkeley... 2010). The two labradorite samples studied from Surtsey, Iceland and Plush, Oregon, both exhibit upward...our stepwise degassing experiment on Surtsey labradorite was released during steps below 600 °C (Fig....4A). The 21Ne step degassing experiment on Plush labradorite, on the other hand, shows a significant downward |  | | Book (edition) | | minerals have been produced commercially from Oregon to the Mexican border and eastward to Maine and...to the eye. In the great lava flows of Idaho, Oregon and Washington occur the many types of agate...feldspar quarries in pegmatite deposits, mines and mine dumps, and from "float" deposits, minerals loose...should always ask permission it may be un- or a mine dvmip. Cleanliness around a camp site and removal...Lincoln Co. Todd's Branch, Mecklenberg Co. Portis mine, Franklin Co. Muddy Creek headwaters, McDowell |  | | Journal (article/letter/editorial) | | California Institute of Technology, Pasadena, CA 91125, USA 2 Present address: Geophysical Laboratory, Carnegie...Institution of Washington, Washington, DC 20008, USA Abstract. Radiation-induced smoky color and associated...0 H20 ~ ND 1,658 Microcline 13757 Elizabeth R Mine, Calif. Or94Ab 6 0.003 None 28.4 M R 900 ° C...Keivy Pegmarite, Kola Peninsula, USSR Or96Ab 4 Lake George, Colorado Or96Ab 4 0.015 0.03 0.04 _...Smoky 0.052 ND OH ND 0 ND 0 ND Labradorite 13761 Lake County, Oregon OrlAb33An66 0.31 None 11.28 |  | | Journal (article/letter/editorial) | | the high market values of natural sunstones in Oregon, a kind of artificially diffused red feldspar exhibited...spectroscopic characteristics of the recolored faceted labradorite were further characterized. The red and light-red...The typical inclusions formed in the faceted labradorite is in the shape of “fire cloud”. The interface...interface of red and light-red faceted labradorite that is in contact with the diffusant is less contaminated...in Surface Recoloring of Faceted Keywords: labradorite; faceted; copper diffusion; recoloring Labradorites |  | | Book (chapter) | | not absorb light in the visible portion of the spectrum and is, therefore, colorless. The onset of absorption...milli- meter-thick crystals of bytownite and labradorite. Unlike potassium feldspars, plagioclases should... iron ferrous exist in yellow labradorite from Lake County, Oregon, with ^0.4 wt % FeO (c/. the spectra...spectra of yellow, gemmy labradorite from Rabbit Hills, Lake County, Oregon. Thickness is 1.00 cm. The...spectra of the same gemmy, yellow labradorite from Rabbit Hills, Oregon as in Figure 2. Thickness 1.00 cm |  | | Journal (issue) | | Gaboury 3 FELDSPAR GEMS Sunstone Moonstone Labradorite GLOWING ROCKS A Fluorescent Exhibit ETHIOPIA’S................... 28 Sunstone, moonstone and labradorite by Bob Jones Glow Rocks ......................quartz cabochons 078-606/09 across the color spectrum. Learn to make these earrings at riogrande.com...wholesale and retail show; T & D Gem Shows; corner of Lake Emory Road and Rte. 441; next to Franklin Ford;...Geological & Mineral Society; Kalamazoo Expo Center; 2900 Lake St.; Fri. 4-8, Sat. 10-6, Sun. 10-5; adults $3, |  | | Journal (issue) | | cornpesltion of ruby-sapphire Red andqreen labradorite feldspar .zoninq and Colour .zoninq and cornpesltion...Microstructure of- cultured blister pearls Red andqreen labradorite feldspar Microstructure cultured blister pearls...Gemm., 2004, 29, 1,8-14 15 2 Red and green labradorite feldspar from Congo Michael S. Krzemnicki &•<"}...and are compared with similar material from Oregon (USA). The specimens from Congo display a deeper colour...gemstones. The studied specimens belong to the labradorite variety of plagioclase feldspar. Microscopically |  | | Journal (issue) | | & GEMOLOGY SPRING 2011 3 NOSY BE 4 km 0 N MINE AREA Ambato MADAGASCAR LLIN S TA C RY TA R Y...mb an ja ~1 0k m n Demantoid Antetezambato mine Figure 2. The Antetezambato garnet deposit is located...located at 575 and 610 nm, clearly visible in the spectrum of the green sample (figure 15, inset); and a...UV wavelengths, evident in the brown sample’s spectrum, is the main cause of its coloration. This absorption...Peaks at 3610, 3581, and 3560 cm −1 in the mid-IR spectrum (reflectance mode) of Antetezambato andradite |  | | Book (edition) | | Corporate Drive, Suite 400, Burlington MA 01803, USA First published 1962 Second edition 1970 Third edition...Canada, Germany, Thailand, Vietnam, the UK and the USA, making this a truly international collaboration...First Edition For two decades, an earlier work of mine – Practical Gemmology – has proved a useful elementary...wood have been replaced by precious opal; in the USA, the woody cell structures of quite large trees have...and in the extensive deposits in the south-western USA, copper sulphides in trachytes (alkaline volcanic |  | | Journal (issue) | | material known as " M a x i x e Beryl" from the Maxixe Mine (Minas Gérais, Brazil). This particular specimen...claimed it as a new mineral in 1933. T h e Maxixe Mine was then a recent discovery. T h e figures regarding...Recently, because of statements by scientists and mine-owners, we are wording our reports in a m a n n...Beryl mine also told me that no one (presumably in Brazil) knew the whereabouts of the Maxixe Mine. Following...the reverse is true) and an unusual narrow-band spectrum in the red a n d yellow regions. I n all three |  | | Journal (article/letter/editorial) | | Oligoclase Anz2 22.3 74.0 3,3 Bakersville, Hawk Mica Mine, North Carolina. EPR Oligoclase An;6 Oligoclase...Boulourio, France EPR Labradorite A n 4 9 - -- - Labrador, Canada NMR Labradorite Anso 50.1 47.5 ...W. EPR, NMR Labradorite Ansz 52.4 44.9 2.7 Labrador, Canada EPR, NMR Labradorite 65.8 33.5 ... 0.7 Lake County, Oregon. EPR 77.2 22.4 0.4 Crystal Bay, Minnesota. EPR An66 Bytownite An77...Oligoclase Figure 1 shows the N M R spectrum of the oligoclase An28. The spectrum consists of broad 23Na and 27A1 |  | | Journal (issue) | | OREGON GEOLOGY published by the Oregon Department of Geology and Mineral Industries VOLUME 49, NUMBER...NUMBER 2 FEBRUARY 1987 OREGON GEOLOGY OIL AND GAS NEWS (ISSN 0164-3304) VOLUME 49, NUMBER 2 Mist Gas...Project FEBRUARY 1987 Published monthly by the Oregon Department of Geology and Mineral Industries (Volumes...Supervisor Second class postage paid at Portland, Oregon. Subscription rates: 1 year $6; 3 years, $15. Single...subscription orders, renewals, and changes of address to Oregon Geology, 910 State Office Building, Portland, OR |  | | Journal (article/letter/editorial) | | 8An0.5Or0.7 <0.01 Fe2O3 this work Pederiniera Mine, São Proctor 1984 Jose da Safira, Minas Gerais,...1982 New Melones Dam, Pohl et al. 1982 Calaveras County, CA; gash veins in metamorphic rock GRR1280 oligoclase...003 FeO Hofmeister and Rossman 1985a Elizabeth R Mine, Pala, Foord et al. 1991 CA; pegmatite GRR1281...3An0.0Or91.7 <0.01 Fe2O3 this work White Queen Mine, Pala, CA; pegmatite Foord et al. 1991 GRR638...obtaining NMR spectra. A labradorite sample (GRR2058, from Ponderosa Mine, Oregon) determined to be anhydrous |  | | Book | | ot all the each has a distinctive absorption spectrum. spectral colours, travels through a gem¬ A...underlying colours of the gemstone. If no part of the spectrum identify the stone. A Chelsea colour filter,...for example, cuts out all of the spectrum less. The “absorption spectrum” produced except red and green...appearance under j ultraviolet in the part of the spectrum that has been X-rays can also aid 1 identification...white and ultraviolet light. 12 The absorption spectrum of zircon. INTRODUCTION The ability of a gemstone |  | | Journal (issue) | | Industry Background image: Miners at the Pala Chief Mine, San Diego Country, California, circa 1903. On the...They are Found zite (201 cts) is from the Oceanview Mine in Southern California; the 0.72-ct benitoite (left...Dallas Gem Mine area, San America’s Royal Gems – Montana and Yogo Sapphires Benito County, California;...Gem Mountain Mine, GranTantalizing Turquoise ite Country, Montana. Photos of gemstones Oregon Sunstone –...Rare and Beautiful American Gemstone and original mine image by Mark Mauthner. Red Beryl – A Very Rare |  | | Book (edition) | | question. Spectral data are provided only where a spectrum is vide history and lore of stones, descriptions...evaporation of saline water (either an ocean or lake) with the consequent precipitation of salts, such...refractive index, specific gravity and optical spectrum (presence or ical absence of diagnostic lines)...from the stone the various color portions of the spectrum have been completely separated. Dispersion (that... SOURCES OF DATA USED 18 TEXT IN SPECTRAL in the spectrum of the sun, respectively at 6870 and 4308 A (Angstrom |  | | Book (edition) | | Spectral data have been provided only where a spectrum is distinctive enough to be useful in identification...evaporation of saline water (either an ocean or lake) with the consequent precipitation of salts, such...refractive index, specific gravity and optical spectrum the radiation and the spacing between the point...ordinary ray. The other ray, which observed in the spectrum of the sun, respectively at 6870 for a uniaxial...from the stone the various color portions of the spectrum have been completely separated. Dispersion is |  | | Book (volume) | | (25.56 ct), Sweet Home Mine, Colorado; colorless scheelite (19.66 ct), Kern County, California; octagonal...Vivid blue matched benitoite gems from San Benito County, California, consisting of 52 benitoites and 75...Deep, spinel red oligoclase feldspar (5.04 ct), Oregon; and three Montana sapphires, violetish blue (2...operators, Morefield Mine, Amelia, VA; Max & Suzy Berchtold, Royal Rainbow Mine, Laytonville, CA; Ralph...Cantlin, Ellis, [D; Jeannette B. Carillo, Gem Center USA, EI Paso, TX; Gary Christopher, The Prospectors Cache |
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