Chalcedony: What Is It?
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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. -
RMSH August 2012 Newsletter.Pdf
VOLUME 47, NO. 8 A UGUST 2012 CHALCEDONY MEETING BY D EAN S AKABE Wednesday This month’s topic is the most worked I call a stone Chalcedony, when it is sort of upon stone in any lapidary operation, translucent and homogeneous in color. August 22 Chalcedony . Chalcedony in a cryptocrys- Such as the Malawi Blue Chalcedony. 6:15-8:00 pm talline form of silica, composed of very Makiki District fine intergrowths of Quartz and Moganite. These are both silica minerals, which differ Park in the respect that quartz has a trigonal Administration crystal structure, while moganite is mono- Building clinic. Chalcedony's standard chemical structure is SiO 2 (Silicon Dioxide). Chalcedony has a waxy luster and is usu- NEXT MONTH ally semitransparent or translucent. It can Wednesday assume a wide range of colors, with the Blue Lace Agate most common seen as white to gray, blue, September 26 or brown ranging from pale to nearly Flourite black. Agates are stones which usually have col- ored layers. These are colored layers of The name "chalcedony" comes from the differently colored layers of Chalcedony. LAPIDARY calcedonius Latin , from a translation from Such as the Blue Lace Agate or Holly Blue Every Thursday khalkedon. the Greek word Unfortu- Agate. 6:30-8:30pm natelly, a connection to the town of Chal- cedon, in Asia Minor could not be found, Forms of Chalcedony are found in all 50 Second-floor Arts but one can always be hopeful. state, occurring in many colors and color and Crafts Bldg combinations. Some of the better known To make things alittle confusing is that ones are: Makiki District Chalcedony and Agate are terms used al- Park most interchangeably, as both are forms of quartz and are both Silicon Dioxide. -
Beads, Pendants COLOURS & EFFECTS
beads, pendants COLOURS & EFFECTS Colours Effects Crystal Crystal Amethyst Light Topaz Aurore Boreale 2x 001 204 226 001 AB2 White Opal Purple Velvet Jonquil Crystal Satin 234 277 213 001 SAT White Alabaster Montana Silk Crystal Matt Finish 281 207 391 001 MAT Rose Water Opal Capri Blue Light Peach Crystal Moonlight 395 243 362 001 MOL Rose Alabaster Sapphire Light Colorado Topaz Crystal Silver Shade 293 206 246 001 SSHA Vintage Rose Light Sapphire Topaz Crystal Golden Shadow 319 211 203 001 GSHA Light Rose Aquamarine Light Smoked Topaz Crystal Copper 223 202 221 001 COP Crystal Rose Light Azore Smoked Topaz 209 Comet Argent Light 361 220 001 CAL Fuchsia Indian Sapphire Mocca White Opal Sky Blue 502 217 286 234 SBL Ruby Pacifi c Opal Smoky Quartz White Opal Star Shine 501 390 225 234 STS Padparadscha Mint Alabaster Sand Opal Crystal Bermuda Blue 542 397 287 001 BBL Fireopal Turquoise Light Grey Opal Crystal Heliotrope 237 267 383 001 HEL Hyacinth Indicolite Black Diamond Crystal Metallic Blue 2x 236 379 215 001 METBL2 Indian Red Caribbean Blue Opal Jet Crystal Vitrail Medium 374 394 280 001 VM Light Siam Blue Zircon Crystal Dorado 2x 227 229 001 DOR2 Dark Red Coral Chrysolite Jet Nut 2x 396 238 280 NUT2 Siam Peridot Jet Hematite 208 214 280 HEM Garnet Erinite Jet Hematite 2x 241 360 280 HEM2 Burgundy Emerald 515 205 Light Amethyst Palace Green Opal 212 393 Violet Opal Olivine 389 228 Violet Khaki 371 550 Tanzanite Lime 539 385 Classic Colours Exclusive Colours WWW.SWAROVSKI.COM/CRYSTALLIZED © 2008 Swarovski AG beads, pendants COLOURS & -
GEOLOGIC SUMMARY of the APPALACHIAN BASIN, with REFERENCE to the SUBSURFACE DISPOSAL of RADIOACTIVE WASTE SOLUTIONS by George W
TEI-791 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY" GEOLOGIC SUMMARY OF THE APPALACHIAN BASIN, WITH;REFERENCE TO THE SUBSURFACE DISPOSAL OF RADIOACTIVE WASTE SOLUTIONS* By George W. Colton June 1961 Report TEI-791 This report is preliminary and ha^;not been edited for conformity with G^logical Survey format and nomenclature. ?1 ^Prepared on behalf of the U. S. Atomic Energy Commission. CONTENTS Abstract* .......................... 5 Introduction. ........................ 7 Purpose of report. ................... 7 Organization of report .................. 7 Location and extent of area. .............. Q Acknowledgments. .................... 10 Geologic framework. ..................... 10 Depositional framework ................. 10 Structural framework .................. llj. Stratigraphy. ........................ 17 Late Precambrian stratified sequence .......... 17 Early Cambrian clastic sequence. ............ 18 Thickness and depth ................ 22 Cambrian-Ordovician carbonate sequence ......... 23 Thickness and depth . , ........... 35 Late Ordovician clastic sequence ............ 35 Thickness and depth ................ Mi- Early Silurian clastic sequence. ............ kk Thickness and depth ................ 51 Silurian-Devonian carbonate sequence .......... 52 Thickness and depth ................ 62 Devonian classic sequence. ............... 63 Thickness and depth ................ 69 Mississippian sequence ................. 70 Thickness and depth ................ 79 Pennsylvanian sequence ................. 79 Waste -
Lexington Quadrangle Virginia
COMMONWEALTH OF VIRGINIA DEPARTMENT OF CONSERVATION AND ECONOMIC DEVELOPMENT DIVISION OF MINERAL RESOURCES GEOLOGY OF THE LEXINGTON QUADRANGLE VIRGINIA KENNETH F. BICK REPORT OF INVESTIGATIONS I VIRGINIA DIVISION OF MINERAL RESOURCES Jomes L. Colver Commissioner of Minerol Resources ond Stote Geologist CHARLOTTESVI LLE, VI RGI N IA 1960 COMMONWEALTH OF VIRGINIA DEPARTMENT OF CONSERVATION AND ECONOMIC DEVELOPMENT DIVISION OF MINERAL RESOURCES GEOLOGY OF THE LEXINGTON QUADRANGLE VIRGINIA KENNETH F. BICK REPORT OF INVESTIGATIONS I VIRGINIA DIVISION OF MINERAL RESOURCES Jomes L. Colver Commissioner of Minerol Resources ond Stote Geologist CHARLOTTESVI LLE, VI RGI N IA 1960 Couuowwoer,rn op Vtncrwre DopenrupNr op Puncnesrs exo Supptv Rrculroxn 1960 DEPARTMENT OF CONSERVATION AND ECONOMIC DEVELOPMENT Richmond. Virginia MenvrN M. SurHnnr,eNn, Director BOARD Vrcron W. Stnwenr, Petersburg, Chairtnan G. Ar,vrn MessnNnunc, Hampton, Viee'Chairman A. Pr,urvrnr BmnNn, Orange C. S. Cenrnn, Bristol ANpnpw A. Fenr,pv, Danville WonrnrrvcroN FauLKNEn, Glasgow SvoNpv F. Slter,r,, Roanoke EnwrN H. Wrr,r,, Richmond Wrr,r,renr P. Wooor,nv. Norfolk CONTENTS Pece Abstract. '"*i"#:;;;;: . : ::: , : ::.:::::::::..::::::. :.::.::::::: ::,r Z Geography 8 Purpose. 4 Previous Work. Present Work and Acknowledgements. 5 Geologic Formations. 6 Introduction. 6 Precambrian System. 6 Pedlar formation 6 Precambrian and Cambrian Systems. 6 Discussion. 6 Swift Run formation 8 Catoctin greenstone. I Unieoiformation...... ......... I Hampton(Harpers)formation. .......... I Erwin (Antietam) quartzite. Cambrian System . I0 Shady (Tomstown) dolomite 10 Rome (Waynesboro) formation.... ll Elbrook formation. 12 Conococheague limestone. l3 Ordovician System. ......., 14 Chepultepeclimestone. .......... 14 Beekmantown formatron. 14 New Market limestone. 15 Lincolnshire limestone. 16 Edinburg formation. 16 Martinsburg shale... 17 SilurianSystem. ......... 18 Clinchsandstone..... .......... 18 Clinton formation. -
Recognized by Fashion Industry Professionals for Their Impeccable
FLATBACK STONES Flatback Stones Recognized by fashion industry professionals for their impeccable light dispersion and extreme durability, Preciosa Flatback Stones come in a rainbow of captivating colors and coatings. Our flagship Chaton Rose MAXIMA can reflect up to 264 unique rays of light, the most of any competing stone on the market, making this the world’s most brilliant flatback. 65 Colors Coatings Numerical Order Crystal Light Topaz Crystal AB 00030 . Crystal 10220 . Smoked Topaz 50630 . Shamrock 00030 10020 200 AB 00030 200 AB . Crystal AB 10330 . Light Colorado Topaz 50730 . Emerald 00030 213 Lav .......... Crystal Lava 10430 . Gold Beryl 51000 . Chrysolite Opal Jet Topaz Crystal Argent Flare 00030 219 Snr .......... Crystal Sunrise 20020 . Light Amethyst 60000 . Aquamarine 23980 10070 242 AgF 00030 231 BlF . Crystal Blue Flare 20030 . Smoked Amethyst 60010 . Aqua Bohemica 00030 234 Ven.......... Crystal Venus 20050 . Amethyst 60100 . Indicolite White Opal Light Colorado Topaz Crystal Velvet* 00030 235 Hon . Crystal Honey 20410 . Tanzanite 60230 . Blue Zircon 01000 10330 279 Vel 00030 237 Lag.......... Crystal Lagoon 20490 . Purple Velvet 60310 . Capri Blue Black Diamond Light Smoked Topaz Crystal Honey 00030 239 BdF.......... Crystal Blond Flare 21110 . Amethyst Opal 70010 . Rose 40010 10210 235 Hon 00030 242 AgF.......... Crystal Argent Flare 23980 . Jet 70020 . Light Rose 00030 244 GdH . Crystal Golden Honey 23980 200 AB . Jet AB 70040 . Indian Pink Smoked Sapphire Smoked Topaz Crystal Golden Honey 00030 251 RdF.......... Crystal Red Flame 23980 230 BrF .......... Jet Brown Flare 70220 . Pink Sapphire 30010 10220 244 GdH 00030 259 PeG . Crystal Peacock Green 23980 232 SiF . Jet Silver Flare 70230 . -
PALEOZOIC STRATIGRAPHIC COLUMN of Central Pennsylvania
PALEOZOIC STRATIGRAPHIC COLUMN of Central Pennsylvania _____________________________________________________________________*Ridge Makers System & Series Formation and Members General Description Llewellyn Formation Cycles of conglomerate or sandstone; underclay coal, shale Pnn. L & N 2000’+ Pottsville Formation* Cycles of conglomerate or sandstone; underclay coal, shale L & M 1400’ Mauch Chunk Grayish red and gray shale M 5000’ Miss. Pocono* Mount Carbon Gray to buff, medium grained, cross-bedded sandstone 1600’ 940’ Beckville Gray to buff, medium grained, cross-bedded sandstone Lower 225’ Spechty Kopf Gray, fine and medium grained sandstone conglomerate 435’ near middle and base Catskill Duncannon Asymmetric, upward-fining fluvial cycles, basal nonred, locally 7250’ 2000’ conglomeratic sandstone is overlain by grayish red sandstone and siltstones Sherman Creek Interbedded grayish red claystone and fine grained, cross- 2400’ bedded sandstone Upper Irish Valley Interbedded, grayish red and olive gray sandstone, siltstone, 2850’ shale, overlain upward-fining cyclic deposits of gray sandstone and red siltstone Trimmers Rock Medium gray siltstone and shale, with fine grained sandstone in 2000’ upper part; graded bedding common Harrell Olive and medium light gray shale 200’ Mahantango Sherman Ridge* Olive gray, fossiliferous, claystone with interbedded fine 1600’ 600’ sandstones which coarsen upward Montebello Olive gray, medium grained, locally conglomeratic, fossiliferous 600’ sandstone, interbedded with siltstone and claystone in upward- -
Toxicological Profile for Silica
SILICA 208 CHAPTER 5. POTENTIAL FOR HUMAN EXPOSURE 5.1 OVERVIEW Silica has been identified in at least 37 of the 1,854 hazardous waste sites that have been proposed for inclusion on the EPA National Priorities List (NPL) (ATSDR 2017). However, the number of sites in which silica has been evaluated is not known. The number of sites in each state is shown in Figure 5-1. Figure 5-1. Number of NPL Sites with Silica Contamination Crystalline Silica • c-Silica is ubiquitous and widespread in the environment, primarily in the form of quartz. Other predominant forms include cristobalite and tridymite. • Sand, gravel, and quartz crystal are the predominant commercial product categories for c-silica. • c-Silica enters environmental media naturally through the weathering of rocks and minerals and anthropogenic releases of c-silica in the form of air emissions (e.g., industrial quarrying and mining, metallurgic manufacturing, power plant emissions) or use in water filtration (quartz sand). SILICA 209 5. POTENTIAL FOR HUMAN EXPOSURE • c-Silica undergoes atmospheric transport as a fractional component of particulate emissions, is virtually insoluble in water and generally settles into sediment, and remains unchanged in soil. • c-Silica is present in air and water; therefore, the general population will be exposed to c-silica by inhalation of ambient air and ingestion of water. • Inhalation exposure is the most important route of exposure to c-silica compounds due to the development of adverse effects from inhaled c-silica in occupational settings. • Individuals with potentially high exposures include workers with occupational exposure to c-silica, which occurs during the mining and processing of metals, nonmetals, and coal, and in many other industries. -
Preciosa Flatback Rhinestones
FLATBACK STONES Flatback Stones Recognized by fashion industry professionals for their impeccable light dispersion and extreme durability, Preciosa Flatback Stones come in a rainbow of captivating colors and coatings. Our flagship Chaton Rose MAXIMA can reflect up to 264 unique rays of light, the most of any competing stone on the market, making this the world’s most brilliant flatback. Colors Coatings Numerical Order Crystal Topaz Crystal AB 00030 . Crystal 10210 . Light Smoked Topaz 50630 . Shamrock 00030 10070 200 AB 00030 200 AB . Crystal AB 10220 . Smoked Topaz 50730 . Emerald 00030 213 Lav .......... Crystal Lava 10330 . Light Colorado Topaz 51000 . Chrysolite Opal Jet Light Colorado Topaz Crystal Argent Flare 00030 219 Snr .......... Crystal Sunrise 10430 . Gold Beryl 60000 . Aquamarine 23980 10330 242 AgF 00030 231 BlF . Crystal Blue Flare 20020 . Light Amethyst 60010 . Aqua Bohemica 00030 234 Ven.......... Crystal Venus 20030 . Smoked Amethyst 60100 . Indicolite FLATBACK STONES White Opal Light Smoked Topaz Crystal Velvet* 00030 235 Hon . Crystal Honey 20050 . Amethyst 60230 . Blue Zircon 01000 10210 279 Vel 00030 237 Lag.......... Crystal Lagoon 20410 . Tanzanite 60310 . Capri Blue Black Diamond Smoked Topaz Crystal Honey 00030 239 BdF.......... Crystal Blond Flare 20490 . Purple Velvet 70010 . Rose 40010 10220 235 Hon 00030 242 AgF.......... Crystal Argent Flare 21110 . Amethyst Opal 70020 . Light Rose 00030 244 GdH . Crystal Golden Honey 23980 . Jet 70040 . Indian Pink Smoked Sapphire Light Gold Quartz Crystal Golden Honey 00030 251 RdF.......... Crystal Red Flame 23980 200 AB . Jet AB 70220 . Pink Sapphire 30010 00520 244 GdH 00030 259 PeG . Crystal Peacock Green 23980 230 BrF .......... Jet Brown Flare 70230 . -
Spring 1984 Gems & Gemology
VOLUME XX SPRING 1984 The cluarterly journal of the Cetiiological Institute of America SPRING 1984 Volume 20 Number 1 TABLE OF CONTENTS EDITORIALS 1 Basil W. Anderson, 1901 -1984 Richard T. Liddicoat, Ir. 2 The Gems & Gemology Most Valuable Article Award Alice S. IZeller FEATURE 4 The Santa Terezinha de Goihs Emerald Deposit ARTICLES 1. P. Cassedanne and D. A. Sauer 14 Pitfalls in Color Grading Diamonds by Machine A. T. Collins . , 22 The Eat'ly History of Gemstone Treatments . 1. Kurt Nassau NOTES 34 'Cobalt-Blue' Gem Spinels AND NEW lames E. Shigley and Carol M. Stockion TECHNIQUES 42 Lepidolite with Simulated Matrix lohn I. IZoivula and C. W. Fryer REGULAR 45 Gem Trade Lab Notes FEATURES 51 Gemological Abstracts 58 Gem News 61 Book Reviews ABOUTTHE COVER: Most Imboratories colorgrade diamonds by comparison with masterstones, a subjective procedure that requires very experiencedpersonnel. In recent years, some laboratories have investigated the possibilities of color grading by machine, to provide a more objective procedure. The problems inherent with color grrrriing by machine are discussed in detail by Dr. A. T. Collins in this issue. The 5.07-ctdiamond on the cover has beengraded D-color (flawless).The stone is courtesy oflack and Elaine Greenspan, Sedona, Arizona. Photo 01984 Harold eL, Erica Van Pelt-Photographers, Los Angeles, California. The color separations for Gems &Gemology are by Effeclive Graphics, Compton, CA. Printing is by Waverly Press, Easton, MD. 07984 Gemological lnslitute of America All rights reserved. ISSN 0016-626X EDITORIAL Editor-in-Chief Editor Editor, Gem Trade Lab Notes STAFF Richard T. -
Volume 43 March 2017 Number 3 April Monthly Meeting
A monthly publication of the Clear Lake Gem & Mineral Society VOLUME 43 MARCH 2017 NUMBER 3 NEXT MEETING: April 17, 2017 TIME: 7:30 p.m. LOCATION: Clear Lake Park Building 5001 Nasa Parkway Seabrook, Texas INSIDE THIS ISSUE APRIL MONTHLY MEETING April Meeting 1- Martian meteorites and the evolution of Mars 2 The program will be presented by Monthly Meeting Thomas Lapen, Professor in the Minutes 2- Board Meeting 4 Earth and Atmospheric Sciences Minutes Department at the University of Houston. He will discuss insights into the duration of igneous Martian Meteorite 4- activity and the nature of magma sources in Mars from analyses Bench Tips 5 of shergottite meteorites – mafic to ultramafic igneous rocks from Mars’ crust. This presentation will summarize some of the 6- recent discoveries about Mars made from the study of Martian Chalcedony 9 meteorites and will discuss some future research directions. This will be a talk for a general audience. Visitors are always welcomed. Upcoming Shows 9 Page 2 MARCH 2017 STONEY STATEMENTS MINUTES OF THE MARCH 20, 2017 MONTHLY MEETING The March meeting was called to order on March 20th at the Clear Lake Park building. Show review and items for next year: · A few vendors felt that we had too many dealers at the show. We would like to keep the quality of the show and increase attendance. · I t was mentioned that the Fredericksburg show was packed. We might want to find out what advertising they did. · We were on the Debra Duncan show, but we aren’t sure how our info got on. -
A Billion Years of Deformation in the Central Appalachians: Orogenic Processes and Products
Downloaded from fieldguides.gsapubs.org on October 15, 2015 The Geological Society of America Field Guide 40 2015 A billion years of deformation in the central Appalachians: Orogenic processes and products Steven J. Whitmeyer Department of Geology and Environmental Science, James Madison University, Harrisonburg, Virginia 22807, USA Christopher M. Bailey Department of Geology, College of William & Mary, Williamsburg, Virginia 23187, USA David B. Spears Virginia Department of Mines, Minerals, and Energy, Division of Geology and Mineral Resources, Charlottesville, Virginia 22903, USA ABSTRACT The central Appalachians form a classic orogen whose structural architecture developed during episodes of contractional, extensional, and transpressional defor- mation from the Proterozoic to the Mesozoic. These episodes include components of the Grenville orogenic cycle, the eastern breakup of Rodinia, Appalachian orogenic cycles, the breakup of Pangea, and the opening of the Atlantic Ocean basin. This fi eld trip examines an array of rocks deformed via both ductile and brittle processes from the deep crust to the near-surface environment, and from the Mesoproterozoic to the present day. The trip commences in suspect terranes of the eastern Piedmont in central Vir- ginia, and traverses northwestward across the Appalachian orogen through the thick- skinned Blue Ridge basement terrane, and into the thin-skinned fold-and-thrust belt of the Valley and Ridge geologic province. The traverse covers a range of deformation styles that developed over a vast span of geologic time: from high-grade metamorphic rocks deformed deep within the orogenic hinterland, to sedimentary rocks of the fore- land that were folded, faulted, and cleaved in the late Paleozoic, to brittle extensional structures that overprint many of these rocks.