Toxicological Profile for Silica
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How to Identify Rocks and Minerals
How to Identify Rocks and Minerals fluorite calcite epidote quartz gypsum pyrite copper fluorite galena By Jan C. Rasmussen (Revised from a booklet by Susan Celestian) 2012 Donations for reproduction from: Freeport McMoRan Copper & Gold Foundation Friends of the Arizona Mining & Mineral Museum Wickenburg Gem & Mineral Society www.janrasmussen.com ii NUMERICAL LIST OF ROCKS & MINERALS IN KIT See final pages of book for color photographs of rocks and minerals. MINERALS: IGNEOUS ROCKS: 1 Talc 2 Gypsum 50 Apache Tear 3 Calcite 51 Basalt 4 Fluorite 52 Pumice 5 Apatite* 53 Perlite 6 Orthoclase (feldspar group) 54 Obsidian 7 Quartz 55 Tuff 8 Topaz* 56 Rhyolite 9 Corundum* 57 Granite 10 Diamond* 11 Chrysocolla (blue) 12 Azurite (dark blue) METAMORPHIC ROCKS: 13 Quartz, var. chalcedony 14 Chalcopyrite (brassy) 60 Quartzite* 15 Barite 61 Schist 16 Galena (metallic) 62 Marble 17 Hematite 63 Slate* 18 Garnet 64 Gneiss 19 Magnetite 65 Metaconglomerate* 20 Serpentine 66 Phyllite 21 Malachite (green) (20) (Serpentinite)* 22 Muscovite (mica group) 23 Bornite (peacock tarnish) 24 Halite (table salt) SEDIMENTARY ROCKS: 25 Cuprite 26 Limonite (Goethite) 70 Sandstone 27 Pyrite (brassy) 71 Limestone 28 Peridot 72 Travertine (onyx) 29 Gold* 73 Conglomerate 30 Copper (refined) 74 Breccia 31 Glauberite pseudomorph 75 Shale 32 Sulfur 76 Silicified Wood 33 Quartz, var. rose (Quartz, var. chert) 34 Quartz, var. amethyst 77 Coal 35 Hornblende* 78 Diatomite 36 Tourmaline* 37 Graphite* 38 Sphalerite* *= not generally in kits. Minerals numbered 39 Biotite* 8-10, 25, 29, 35-40 are listed for information 40 Dolomite* only. www.janrasmussen.com iii ALPHABETICAL LIST OF ROCKS & MINERALS IN KIT See final pages of book for color photographs of rocks and minerals. -
The Dependence of the Sio Bond Length on Structural Parameters in Coesite, the Silica Polymorphs, and the Clathrasils
American Mineralogist, Volume 75, pages 748-754, 1990 The dependence of the SiO bond length on structural parameters in coesite, the silica polymorphs, and the clathrasils M. B. BOISEN, JR. Department of Mathematics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, U.S.A. G. V. GIBBS, R. T. DOWNS Department of Geological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, U.S.A. PHILIPPE D' ARCO Laboratoire de Geologie, Ecole Normale Superieure, 75230 Paris Cedex OS, France ABSTRACT Stepwise multiple regression analyses of the apparent R(SiO) bond lengths were com- pleted for coesite and for the silica polymorphs together with the clathrasils as a function of the variables};(O), P (pressure), f,(Si), B(O), and B(Si). The analysis of 94 bond-length data recorded for coesite at a variety of pressures and temperatures indicates that all five of these variables make a significant contribution to the regression sum of squares with an R2 value of 0.84. A similar analysis of 245 R(SiO) data recorded for silica polymorphs and clathrasils indicate that only three of the variables (B(O), };(O), and P) make a signif- icant contribution to the regression with an R2 value of 0.90. The distribution of B(O) shows a wide range of values from 0.25 to 10.0 A2 with nearly 80% of the observations clustered between 0.25 and 3.0 A2 and the remaining values spread uniformly between 4.5 and 10.0 A2. A regression analysis carried out for these two populations separately indicates, for the data set with B(O) values less than three, that };(O) B(O), P, and };(Si) are all significant with an R2 value of 0.62. -
Crystalline Silica, Cristobalite (CAS No
Crystalline Silica, Quartz (CAS No. 14808-60-7) Crystalline Silica, Cristobalite (CAS No. 14464-46-1) Crystalline Silica, Tridymite (CAS No. 15468-32-3) Diatomaceous earth (CAS No. 61790-53-2) This dossier on crystalline silica, quartz, cristobalite and tridymite and diatomaceous earth presents the most critical studies pertinent to the risk assessment of these substances in their use in drilling muds and cement additives. This dossier does not represent an exhaustive or critical review of all available data. The majority of information presented in this dossier was obtained from the ECHA database that provides information on chemicals that have been registered under the EU REACH (ECHA). Where possible, study quality was evaluated using the Klimisch scoring system (Klimisch et al., 1997). For the purpose of this dossier, crystalline silica, quartz (CAS No. 14808-60-7) has been reviewed as representative of crystalline silica cristobalite and tridymite. Crystalline silica, quartz is also considered representative of diatomaceous earth, as they both consist mainly of silicon dioxide. Screening Assessment Conclusion – Crystalline silica, quartz, cristobalite and tridymite and diatomaceous earth are classified as tier 1 chemicals and require a hazard assessment only. 1 BACKGROUND Crystalline silica is a common mineral found in the earth's crust. Materials like sand, stone, concrete and mortar contain crystalline silica. It is also used to make products such as glass, pottery, ceramics, bricks and artificial stone. Silica, in the form of sand, is used as the main ingredient in sand casting for the manufacture of metallic components in engineering and other applications. The high melting point of silica enables it to be used in such applications. -
Understanding the Art of Quartz
AIA & IDCEC Continuing Education Program UNDERSTANDING THE ART OF QUARTZ PRESENTED BY: AND 1 Hanwha L&C | Surfaces is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES) and Interior Designers Continuing Education Council (IDCEC). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members or to IDCEC for IIDA, ASID or IDC members. Certificates of Completion for both members and non- members are available upon request. This program is registered with AIA/CES and IDCEC for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA or the IDCEC of any material of construction or any method or manner of handling, using, distributing or dealing in any material or product. Questions related to specific materials, methods and services will be addressed at the conclusion of this presentation. This presentation is protected by US and International copyrights laws. Reproduction, distribu- tion, display and use of the presentation without written permission of the speaker is prohibited. Hanwha L&C | Surfaces 2016. 2 AIA & IDCEC Continuing Education Program ∆ Format: Presented f2f in real-time ∆ Course Credit: ◊ AIA: 1 Learning Unit (LU) ◊ Course #: 004QS ◊ IDCEC: .1 Health & Safety ◊ Course #: 40276 ◊ RAIC: 1 Self-Reporting Hour Δ Completion Certificate: ◊ A copy will be provided to you by email, fax, or mail upon request. 3 Learning Objectives ∆ Gain knowledge about natural quartz surfacing: ◊ Composition and Uses ◊ Product Characteristics ◊ Manufacturing and Fabrication ◊ Application and Design Options 4 INTRODUCTION TO QUARTZ Quartz Facts ∆ Quartz is the 4th hardest crystalline mineral on Earth, and it is found abundantly all over the world in a variety of forms. -
Bedrock Geology Glossary from the Roadside Geology of Minnesota, Richard W
Minnesota Bedrock Geology Glossary From the Roadside Geology of Minnesota, Richard W. Ojakangas Sedimentary Rock Types in Minnesota Rocks that formed from the consolidation of loose sediment Conglomerate: A coarse-grained sedimentary rock composed of pebbles, cobbles, or boul- ders set in a fine-grained matrix of silt and sand. Dolostone: A sedimentary rock composed of the mineral dolomite, a calcium magnesium car- bonate. Graywacke: A sedimentary rock made primarily of mud and sand, often deposited by turbidi- ty currents. Iron-formation: A thinly bedded sedimentary rock containing more than 15 percent iron. Limestone: A sedimentary rock composed of calcium carbonate. Mudstone: A sedimentary rock composed of mud. Sandstone: A sedimentary rock made primarily of sand. Shale: A deposit of clay, silt, or mud solidified into more or less a solid rock. Siltstone: A sedimentary rock made primarily of sand. Igneous and Volcanic Rock Types in Minnesota Rocks that solidified from cooling of molten magma Basalt: A black or dark grey volcanic rock that consists mainly of microscopic crystals of pla- gioclase feldspar, pyroxene, and perhaps olivine. Diorite: A plutonic igneous rock intermediate in composition between granite and gabbro. Gabbro: A dark igneous rock consisting mainly of plagioclase and pyroxene in crystals large enough to see with a simple magnifier. Gabbro has the same composition as basalt but contains much larger mineral grains because it cooled at depth over a longer period of time. Granite: An igneous rock composed mostly of orthoclase feldspar and quartz in grains large enough to see without using a magnifier. Most granites also contain mica and amphibole Rhyolite: A felsic (light-colored) volcanic rock, the extrusive equivalent of granite. -
Fall 2015 Gems & Gemology
FALL 2015 VOLUME LI THE UARTERLY JOURNAL OF THE GEMOLOGICAL INSTITUTE OF AMERICA Colombian Trapiche Emeralds Large Colorless HPHT-Grown Synthetic Diamonds Diamonds from the Letšeng Mine Fall 2015 VOLUME 51, No. 3 EDITORIAL 221 Trapiche and More... Duncan Pay FEATURE ARTICLES 222 Colombian Trapiche Emeralds: Recent Advances in Understanding Their Formation Isabella Pignatelli, Gaston Giuliani, Daniel Ohnenstetter, Giovanna Agrosì, pg. 254 Sandrine Mathieu, Christophe Morlot, and Yannick Branquet Proposes a model for trapiche emerald formation based on petrographic, spectroscopic, and chemical examination. 260 Large Colorless HPHT-Grown Synthetic Gem Diamonds from New Diamond Technology, Russia Ulrika F.S. D’Haenens-Johansson, Andrey Katrusha, Kyaw Soe Moe, Paul Johnson, and Wuyi Wang pg. 270 Examines a new source of colorless and near-colorless gem-quality HPHT synthetic diamonds using spectroscopic and gemological analysis. 280 Letšeng’s Unique Diamond Proposition Russell Shor, Robert Weldon, A.J.A. (Bram) Janse, Christopher M. Breeding, and Steven B. Shirey Explores the history, geology, and current production of this unique source of large diamonds. NOTES AND NEW TECHNIQUES 300 Origin Determination of Dolomite-Related White Nephrite through Iterative-Binary Linear Discriminant Analysis Zemin Luo, Mingxing Yang, and Andy H Shen A technique for origin identification based on statistical analysis and LA-ICP-MS spectrometry. pg. 293 REGULAR FEATURES 312 Lab Notes Unusual graining structure in pink diamond • Yellow HPHT-treated rough diamond -
Minnesota's Mineral Resources
CHAPTER • 9 Minnesota's Mineral Resources IN MINNESOTA the production of iron ore is far more valuable economically than the total of all other mineral products, but im portant industries are based on Minnesota's other geological forma tions as well. Architectural, monumental, and structural stone are produced from granite, limestone, dolomite, and other Minnesota rocks. Gravel and sand are excavated and processed, and clay is used for many ceramic products. :Manganese in important amounts occurs in the iron ores of the Cuyuna district. Finally, although they are often not thought of as mineral products, two of our most im portant mineral resources are water and soil. The iron ores and mining operations of the Mesabi, Vermilion, and Cuyuna iron-bearing districts and of the southeastern lYlinnesota counties will be discussed in detail in later chapters, but a few sta tistics on Minnesota's iron ore industry may remind us how impor tant this geological heritage is. The following is an estimate of Min nesota's iron ore reserves, made on lYlay 1, 1961: Gross Tons Mesabi Range 500,799,179 Vermilion Range 9,755,974 Cuyuna Range 36,530,000 Fillmore County 'il,860,337 Total iron ore 549,945,490 172 MI NESOTA'S MINERAL RESOURCES The total production of iron ore in Minne ota to January 1, 1962, was 2,529,737,553 tons. Total taxes paid on iron ore to January 1, 1961 , were approximately $1,257,448,400, a very important source of funds for the state government. Slightly over 60 per cent of the total iron ore produced in the United States has come from l\1inne- ota. -
Symposium on Agate and Cryptocrystalline Quartz
Symposium on Agate and Cryptocrystalline Quartz September 10 – 13, 2005 Golden, Colorado Sponsored by Friends of Mineralogy, Colorado Chapter; Colorado School of Mines Geology Museum; and U.S. Geological Survey 2 Cover Photos {top left} Fortification agate, Hinsdale County, Colorado, collection of the Geology Museum, Colorado School of Mines. Coloration of alternating concentric bands is due to infiltration of Fe with groundwater into the porous chalcedony layers, leaving the impermeable chalcedony bands uncolored (white): ground water was introduced via the symmetric fractures, evidenced by darker brown hues along the orthogonal lines. Specimen about 4 inches across; photo Dan Kile. {lower left} Photomicrograph showing, in crossed-polarized light, a rhyolite thunder egg shell (lower left) a fibrous phase of silica, opal-CTLS (appearing as a layer of tan fibers bordering the rhyolite cavity wall), and spherulitic and radiating fibrous forms of chalcedony. Field of view approximately 4.8 mm high; photo Dan Kile. {center right} Photomicrograph of the same field of view, but with a 1 λ (first-order red) waveplate inserted to illustrate the length-fast nature of the chalcedony (yellow-orange) and the length-slow character of the opal CTLS (blue). Field of view about 4.8 mm high; photo Dan Kile. Copyright of articles and photographs is retained by authors and Friends of Mineralogy, Colorado Chapter; reproduction by electronic or other means without permission is prohibited 3 Symposium on Agate and Cryptocrystalline Quartz Program and Abstracts September 10 – 13, 2005 Editors Daniel Kile Thomas Michalski Peter Modreski Held at Green Center, Colorado School of Mines Golden, Colorado Sponsored by Friends of Mineralogy, Colorado Chapter Colorado School of Mines Geology Museum U.S. -
Stishovite and Seifertite in Lunar Meteorite Northwest Africa 4734
71st Annual Meteoritical Society Meeting (2008) 5058.pdf FIRST EVIDENCE OF HIGH PRESSURE SILICA: STISHOVITE AND SEIFERTITE IN LUNAR METEORITE NORTHWEST AFRICA 4734. H. Chennaoui Aoudjehane1-2, A. Jambon2 1Université Hassan II Aïn Chock, Laboratoire Géosciences, BP 5366 Maârif Casa- blanca Morocco (e-mail: [email protected]), 2Université Pierre et Marie Curie-Paris6 and IPGP Laboratoire MAGIE, Case 110, 4 place Jussieu, 75252 Paris France. Introduction: Silica is a rare phase in lunar rocks; it has been described as either quartz, cristobalite and/or tridymite [1]. Northwest Africa 4734, is an uncommon type of lunar rock, which may be launched paired with the LaPaz Icefield Lunar Mare basalts found in 2002-03 in Antarctica [2-6], it is a coarse grained rock of basaltic composition, exhibits a number of sig- nificant shock features, such as PDFs, extensive fracturation of pyroxene, impact melt pockets and transformation of plagioclase to maskelynite; silica is present as a minor phase. Analytical procedures: We studied the speciation of silica polymorphs to characterize the shock, using SEM imaging, Ra- man spectroscopy, CL imaging and spectroscopy. Further details can be found in [7]. Results: According to the CL spectra [7-9], cristobalite, tridymite, high-pressure silica glass, stishovite and seifertite, are all present. Special emphasis is made on stishovite and seifertite, which, like in shergottites, exhibit specific textural features [7]. Cathodoluminescence spectra characteristic of high-pressure sil- ica phases: glass, stishovite and seifertite have been recorded in addition to the original low-pressure phases. The remanence of cristobalite and tridymite underscores a significant heterogeneity of the shock supported by the rock. -
Long Suspected Theory About the Moon Holds Water 14 June 2018
Long suspected theory about the moon holds water 14 June 2018 Moganite was found in only one of those 13 samples, confirming the team's theory that it could not have formed in the African desert. "If terrestrial weathering had produced moganite in the lunar meteorite, there should be moganite present in all the samples that fell to Earth around the same time. But this was not the case," says Kayama. Photograph of lunar meteorite NWA 2727. Credit: Masahiro Kayama, Tohoku University A team of Japanese scientists led by Masahiro Kayama of Tohoku University's Frontier Research Institute for Interdisciplinary Sciences, has discovered a mineral known as moganite in a lunar Sectional photograph of lunar meteorite NWA 2727. meteorite found in a hot desert in northwest Africa. Credit: Masahiro Kayama, Tohoku University This is significant because moganite is a mineral that requires water to form, reinforcing the belief that water exists on the Moon. He adds that part of the moganite had changed into the high-pressure SiO2 minerals stishovite and "Moganite is a crystal of silicon dioxide and is coesite, which he believes was most likely formed similar to quartz. It forms on Earth as a precipitate through heavy impact collisions on the Moon when alkaline water including SiO2 is evaporated under high pressure conditions," says Kayama. This is the first time that moganite has been "The existence of moganite strongly implies that detected in lunar rocks. The researchers say the there is water activity on the Moon." meteorites probably came from an area of the Moon called Procellarum Terrane, and that the Kayama and his team analyzed 13 of the lunar moganite was formed through the process of water meteorites using sophisticated methods to evaporation in strong sunlight. -
Slabs | Tiles | Accessories Bring Your Vision to Life
SLABS | TILES | ACCESSORIES BRING YOUR VISION TO LIFE ¨STONES MARBLE ONYX LIMESTONE GRANITE TRAVERTINE QUARTZITE SEMI-PRECIOUS SPECIALTY STONE SLATE AGGLOMERATES MOSAICS MAGNUM OPUSTONE There is nothing quite like it. When you encounter the ideal stone, nothing else even comes close. More than just color, tone, texture and complexity, our stone must possess a certain character that elevates it and brings it to life. Richness, depth, a soul. We travel the globe to source the finest possible stones in a relentless pursuit of perfection. From quarry to quarry, we seek out and purchase the very best, the most distinctive, the only stones worthy of being Opustone. And we back it up with phenomenal industry-leading service, the kind of service you would only expect from a company that brings you the finest stones on earth. After all, we are not merely distributors of natural and manufactured stone. We assemble a distinctive, natural palette of materials for the design and creation of unique living spaces. Our stones were destined to be lived with. Nothing but Opustone will ever do. ¨GRANITE ¨MARBLE LEGENDARY AND TIMELESS. DESIGNED BY NATURE TO DEFINE THE SPACES WHERE HISTORY TAKES PLACE. ONYX¨ DEEP AND PONDEROUS. LOOK CLOSELY AND DISCOVER VAST WORLDS WITHIN. ¨LIMESTONE DEFINE YOUR SPACE WITH SUBTLE COLORS AND COMPLEX TEXTURES. BEAUTY ENDURES, SOLID AND ETERNAL, GRANITE¨ WAVES OF COLOR MELDING INTO ONE. COMPLEXITY IN ITS MOST SIMPLE FORM. ¨TRAVERTINE QUARTZITE¨ A DRAMATIC EXPERIENCE IN RICH TONES AND STRIKING DETAIL. ¨SEMI-PRECIOUS TRANSCENDING TIME WHERE. VISIONS BECOME REALITY. SPECIALTY STONE¨ ELEGANCE THAT GOES WELL BEYOND THE GOES WELL BEYOND ELEGANCE THAT OF THE ORDINARY. -
List of Stones
LIST OF STONES cognac colour diamond DN prehnite PR diamond D pyrite PY, MA heat enhanced black diamond DB quartzite QW amazonite AZ treated quartz RA amber AMB, R rhodolite RHL, RHG, RHP amethyst AM, AMP rock crystal RC, BK aquamarine AQ rose quartz RQ black onyx ON, O ruby RU black spinel SPB, ME sapphire SA black/white agate cameo CAM smoky quartz SQ blue topaz BTP, TPA smoky quartz/mother of pearl doublet P carnelian CAR, K tanzanite TZ chalcedony CA tourmalinated quartz BRU chrysoprase CH treated quartz RA citrine CI, CIG, CIC, CIY treated topaz, paraiba blue TPP cognac quartz CQ treated topaz, pink TPK garnet GR, GA treated pink sapphire PSA green quartz GQ, GAM turquoise TQ grey moonstone MSG whisky quartz WQ, BQ hematite HEM white agate AGW iolite IO, IOB white opal WOP labradorite LBG black crystal NCK lapis lazuli LP, L black cubic zirconia CZK lemon quartz LQ blue cubic zirconia CZB light colour amethyst PAM brown cubic zirconia BCZ moonstone MS champagne coloured cubic zirconia CCZ nephrite-jade NJA cubic zirconia CZ orange moonstone MSO dark blue synthetic spinel SSB peridot PE, PEA dark green cubic zirconia CZN pink opal POP green cubic zirconia GCZ pink rock PRO, RNI grey crystal NGY pink sapphire PSA honey cubic zirconia CZM pink tourmaline TU lavender cubic zirconia LCZ light blue cubic zirconia CZA copper coloured cultured pearl PRC, RRC light blue synthetic spinel SSL golden mabe cultured pearl PGO light rose cubic zirconia TCZ green cultured pearl PG lime cubic zirkonia CZL grey faceted cultured pearl PSG orange cubic