DOCSLIB.ORG

Analysis of Gold Jewellery Artifacts CHARACTERIZATION of ANCIENT GOLD SOLDERS by PIXE

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Analysis of Gold Jewellery Artifacts CHARACTERIZATION of ANCIENT GOLD SOLDERS by PIXE Analysis of Gold jewellery Artifacts CHARACTERIZATION OF ANCIENT GOLD SOLDERS BY PIXE G. Demortier L.A.R.N., Facultés Universitaires de Namur, B-5000 Namur, Belgium For many years it bas been uridely assumed that in amfacts from antiquity in whíchparts were joined by soldering or brazing, such solders or brazes were cadmium free. Recent analyses usingparticle inducedX- orgamma-ray emission techniques have castdoubt upon this hypothesis. When analyzing jewellery items the ideal method of analysis time (10 -9 to 10 -20 s) and they may be called prompt reactions by should be quantitative, accurate, reliable, topographical, but above comparison with delayed emission of particles and/or radiations all non-destructive and suitable to give the chemical composition obtained in activation analysis: the emission of photons (X and/or of different parts of a piece of jewellery without any sampling, even 'y-ray) and charged particles induced by low energy charged particle at microscopic level. bombardment stops when the incident beam is stopped. Particle Induced X-ray Emission (PIXE) and Particle Induced Rutherford elastic scattering (mainly in the reverse direction) has Gamma-ray Emission (PIGE, sometimes called PIGME), are two been successfully used in material analysis for quantitative techniques used specially with the objects under investigation at determination of heavy elements in matrices of low atomic weight. atmospheric pressure, which exhibit most of these qualities. When At a given reverse angle, the energy of the scattered particles used simultancously, these two techniques are capable of solving depends only on the ratio of the mass of this incident projectile to most of the problems of interference often present in prompt that of the nucleus collided with: the greater is the mass of the target physical methods of analysis. nucleus the greater is also the energy of the scattered particle. This The physical principles of elemental analysis of solids using kind of interaction does not change the nature of the collided nuclei. prompt signals induced during the irradiation of the objects with The second type of reaction (emission of charged particles other projectiles heavier than electrons are described followed by it than the incident one) may give analytical information when the discussion of the application of these principles for topographical incident particles have an energy which is sufficient to cross the analyses of gold jewellery items. Special attention is focussed on the Coulomb barrier of the target nucleus. The analytical interest of this determination of the chemical composition of narrow regions type of reaction is thus restricted to the analysis of elements of low situated at solders evident or expected from the construction of the atomic weight, and mainly for lithium, boron, carbon and nitrogen item. for which the limitofdetection lies in the 10 tg/gregion. This kind A new approach to ancient gold brazing with regard to the of interaction gives rise to a transmutation of the collided nucleus. presence of cadmium is discussed. It takes into account recent Both these abovementioned reactions are then of little interest observations obtained from experiments performed to attempt to for the purposes of the analysis of elements in heavy matrices such rediscover a possible ancient technology for the fabrication of as those contained in gold artifacts. brazing alloys involving only rudimentary means, that is the use of The Coulomb repulsion between the incident particle and a amixture of gold (or electrum) and natural cadmium mineral, the positive atomic nucleus of the material under analysis does not allow colour of which is close to that of gold, in a charcoal furnace. the proton to penetrate in heavy nuclei to eject particles. Fortunately, when the emission of such massive particles is Prompt Analytical Techniques forbidden, the quantum mechanical behaviour of nuclear Let us briefly consider from an analytical point of view the interactions allows -y-ray emission, even when the Coulomb barrier physical principles of prompt nuclear and atomic interactions does not allow the incident partide to collide with the nucleus. The induced by the bombardment of an object with particles the energy parameters governing this kind of reaction have been extensively of which lies in the MeV range. studied during the beginning of the second half of this century and When protons of energy in the MeV range interact with the identification of nearly all the chemical elements by energy atomic components of a sample, four types of reactions useful for dispersive photon detectors is nowpossible (1). The elements used analytical purposes may be produced: in gold jewellery include gold, topper, silver, zint, cadmium and (1) Elastic scattering of the incident particles iron (encountered either as a component or as an impurity) and, in (2) Nuclearreactions giving rise to emission of charged particles the case of modern sophisticated materials, nickel, germanium, (3) Coulomb excitation or resonant absorption immediately rhodium, palladium and platinum. When the incident proton followed by 'y-ray emission energy is increased from < 3 to up to 10 MeV, transmutation of (4) Ionization of electrons from their innershells followed by hard elements may then be induced and residual activity of irradiated X-ray emission. samples expected (2). This phenomenon is used for analytical All the signals from these reactions are produced in a very short purposes but the delayed activity of the sample is often undesirable. GoldBull., 1984, 17,(1) 27 The limits of detection by prompty-ray analysis are better than ionizations give rise to 5 isolated X-ray peaks: LQ, La, Li, L(^, Ly 1 per cent for all of the above mentioned elements and for a time which are more intense than K lines and thus more valuable for of bombardment of less than 1h and when no major interference accurate analysis. The ratios of the intensities of these lines are well is suspected. established and do not vary with the chemical environment of the This sensitivity is often sufficient to determine the elements. The author has written in depth on the treatment of PlXE concentrations of the most abundant elements of the alloy but the data elsewhere (3,4). In Table I are gathered the most useful shape of the y-ray spectrum with an important `background' from the long tail Compton scattering does not allow sufficient accuracy to be reached due to statistical uncertainty on the determination Table 1 of the areas of each characteristic peak. Figure 1 gives an illustration CharacteristicX:rays Usetul br analysis of Metals in Gold of such a spectrum recorded when a modern soldering alloy (75 Jeweltery gold! 3 silver/ 8 topper/ 2 zint/ 12 cadmium per cent is irradiated in a beam of 3 MeV protons). These reactions leading to the emission X ray I Interferences ofy-rays may be used for the characterization of the most abundant components of all materials but they are especially useful for the Element line energy, main secondary analysis of lithium, boron, beryllium, fluorine, sodium, keV element energy, magnesium and aluminium in all kinds of matrices: the limit of keV detection for all these light elements is in the range of 10 .tg/g in Fe Ka 6,40 Mn 8:49 Dy,Sm materials whose matrices are composed of elements of high atomic K(3 7.05 Co 6.93 mass. The use of the fourth prompt phenomenon (X ray production) Ni Ka 7.47 Dy; Eu solves the problem of lack of accuracy for the analysis of heavy and Kp 8.30 W, Tm medium mass elements. When each proton loses its energy in the Cu Ka 8.05 Er, Ta, Tb thick sample, it removes electrons from their specific shells. After Kp 8.80 Os, Lu, Hg a hole is created in a K or L atomic shell, electronic rearrangements occur with emission of K X-rays (and also Auger electrons Zn Ka 8.64. Au 8.50 Re, Yb 9.65 Au 9.70 Ta,W particularly for elements of low atomic mass). For the medium mals Kp elements, it is possible to observe two X-ray lines (Ka and K(i) in Ge Ka 9.85 Hg 9.98 W a good Si(Li) detector; for heavier elements, four lines (Ka, Ka z , KR. 11.10 Pt 11.10 Po, Pb K13, and K(3 2 ) may be detected. For heavy elements L shell Pd Ka 21.10 To Kol 23.80 In 24.00 K02. 24.30 In 24.20 Ag Ka 22.15 Ru 22.07 24.94 Sn 25.05 KP, Kat 25.45. Sn 25.27 Cd. Ka 23.15 Rb 23.16 26.10 Sb. 26,10 K111 Kat 26,64 Sb 26.40 L' 8:27 Cu 8.05 Lei 9A0 in 9.98 Ga Lil • 8977' Ge 0.85 Lp 11.10 Ge 11.10 Se ly 12.95 Se, Br Au Lt 8.50 zn 864 La 970 29.85 .Ge 3.85 Lq 10.30 TI 10.27 G .MI t4 FIPY ENERGY keV L3 11.50 Se, As, Pb, Eig.1 Gamina-rayspetttvmobtainedduringthehradiátionwith3MeV proton of a modern gold braae.contaiáing gold, eiher, eopper, eadtniuny Hg, Mg and zins LY 13.38 Rb 28 GoidBuil , 1984, 17, (1) (b) ,rN WFZ F lu. X-9AV ENERGY, keY Fig. 2(a) -tay spectrum obtained during thé irradiation oFa pure gold sai»pe (b) Enlargetnent of tli spectrum shown in Fig. 2(a) ut the vertical scale. Note the fine characteristic X-ray Tinesanti the`broaden ng oftheX-ray lines. at: the bottoni of In and lui (e) X-ray spectrum obtained during, the irradianon of a cadmium- containing so4dër. The spectrum i recorded usinga fod of zint between the atuple anti the de eetor, givlug rise to zint lines.by fluorescente.
Load more

Recommended publications
  • Ancient Jades Map 3,000 Years of Prehistoric Exchange in Southeast Asia
    Ancient jades map 3,000 years of prehistoric exchange in Southeast Asia Hsiao-Chun Hunga,b, Yoshiyuki Iizukac, Peter Bellwoodd, Kim Dung Nguyene,Be´ re´ nice Bellinaf, Praon Silapanthg, Eusebio Dizonh, Rey Santiagoh, Ipoi Datani, and Jonathan H. Mantonj Departments of aArchaeology and Natural History and jInformation Engineering, Australian National University, Canberra ACT 0200, Australia; cInstitute of Earth Sciences, Academia Sinica, P.O. Box 1-55, Nankang, Taipei 11529, Taiwan; dSchool of Archaeology and Anthropology, Australian National University, Canberra ACT 0200, Australia; eDepartment of Ancient Technology Research, Vietnam Institute of Archaeology, Hanoi, Vietnam; fCentre National de la Recherche Scientifique, Unite´Mixte de Recherche 7528, 27 Rue Paul Bert, 94204 Ivry-sur-Seine, France; gDepartment of Archaeology, Silpakorn University, Bangkok 10200, Thailand; hArchaeology Division, National Museum of the Philippines, Manila, Philippines; and iSarawak Museum, Kuching, Malaysia Edited by Robert D. Drennan, University of Pittsburgh, Pittsburgh, PA, and approved October 5, 2007 (received for review August 3, 2007) We have used electron probe microanalysis to examine Southeast Japanese archaeologist Kano Tadao (7) recognized four types of Asian nephrite (jade) artifacts, many archeologically excavated, jade earrings with circumferential projections that he believed dating from 3000 B.C. through the first millennium A.D. The originated in northern Vietnam, spreading from there to the research has revealed the existence of one of the most extensive Philippines and Taiwan. Beyer (8), Fox (3), and Francis (9) also sea-based trade networks of a single geological material in the suggested that the jade artifacts found in the Philippines were of prehistoric world. Green nephrite from a source in eastern Taiwan mainland Asian origin, possibly from Vietnam.
    [Show full text]
  • Piece Mold, Lost Wax & Composite Casting Techniques of The
    Piece Mold, Lost Wax & Composite Casting Techniques of the Chinese Bronze Age Behzad Bavarian and Lisa Reiner Dept. of MSEM College of Engineering and Computer Science September 2006 Table of Contents Abstract Approximate timeline 1 Introduction 2 Bronze Transition from Clay 4 Elemental Analysis of Bronze Alloys 4 Melting Temperature 7 Casting Methods 8 Casting Molds 14 Casting Flaws 21 Lost Wax Method 25 Sanxingdui 28 Environmental Effects on Surface Appearance 32 Conclusion 35 References 36 China can claim a history rich in over 5,000 years of artistic, philosophical and political advancement. As well, it is birthplace to one of the world's oldest and most complex civilizations. By 1100 BC, a high level of artistic and technical skill in bronze casting had been achieved by the Chinese. Bronze artifacts initially were copies of clay objects, but soon evolved into shapes invoking bronze material characteristics. Essentially, the bronze alloys represented in the copper-tin-lead ternary diagram are not easily hot or cold worked and are difficult to shape by hammering, the most common techniques used by the ancient Europeans and Middle Easterners. This did not deter the Chinese, however, for they had demonstrated technical proficiency with hard, thin walled ceramics by the end of the Neolithic period and were able to use these skills to develop a most unusual casting method called the piece mold process. Advances in ceramic technology played an influential role in the progress of Chinese bronze casting where the piece mold process was more of a technological extension than a distinct innovation. Certainly, the long and specialized experience in handling clay was required to form the delicate inscriptions, to properly fit the molds together and to prevent them from cracking during the pour.
    [Show full text]
  • A Study on Ancient Artifacts Around Badami Hill and Their Correlation with the Natural Rock Arch Of
    A Study on Ancient Artifacts Around Badami Hill and Their Correlation with the Natural Rock Arch of Sidlaphadi SHORT REPORT PRADIPTA BANERJEE MAYUR BAJAJ *Author affiliations can be found in the back matter of this article ABSTRACT CORRESPONDING AUTHOR: Pradipta Banerjee The Badami hill of Bagalkot district, Karnataka, India, houses a large rock arch termed Dayananda Sagar University, IN “Sidlaphadi” that was used as a shelter by primitive man. The hill was searched to [email protected] find any prehistoric artifact that would act as a directional marker towards the arch. An interesting structure was noted in one of the natural caves near the southwestern part of the hill at 15°55’06”N latitude and 75°41’02”E longitude. A miniature replica TO CITE THIS ARTICLE: of the arch was carved onto the floor of the cave. The axis of the miniature bridge Banerjee, P and Bajaj, M. 2021. made an angle of 28.5 ± 1.5° with the 75°41’02”E longitude. The axis, upon extension A Study on Ancient Artifacts eastwards at the defining angle reaches the northern slope of Sidlaphadi. The authors Around Badami Hill and Their also located a megalithic stone arrangement in the northern part of the hill that had Correlation with the Natural a pointed capstone and was thought to be oriented towards the rock arch. The stone Rock Arch of Sidlaphadi. Ancient Asia, 12: 9, pp. 1–9. arrangement was in the same latitude as that of the Sidlaphadi site, but the capstone DOI: https://doi.org/10.5334/ ° ° was oriented 22 E towards the winter solstice sunrise at 112.5 azimuth.
    [Show full text]
  • Gomposition and Occurrence of Electrum Atthe
    L37 The Canadian M inerala g i st Vol.33,pp. 137-151(1995) GOMPOSITIONAND OCCURRENCEOF ELECTRUM ATTHE MORNINGSTAR DEPOSIT, SAN BERNARDINOCOUNTY, GALIFORNIA: EVIDENCEFOR REMOBILIZATION OF GOLD AND SILVER RONALD WYNN SIIEETS*, JAMES R. CRAIG em ROBERT J. BODNAR Depanmen of Geolngical Sciences, Virginin Polytechnic h stitate and Stale (Jniversity, 4A44 Dening Hall, Blacl<sburg, Virginin 24060, U.S-A,. Arsrnacr Elecfum, acanthiteand uytenbogaardtite have been examined from six depthswithin the tabular quartzt calcite sockwork and breccia-filled veins in the fault-zone-hostedMorning Star depositof the northeasternMojave Desert, Califomia. Six distinct types of electrum have been identified on the basis of minerat association,grain moryhology and composition. Two types, (1) p1'rite-hostedand (2) quartz-hostedelectrum, occur with acanthite after argentite and base-metalsulfide minerals in unoxidized portions of the orebody; the remaining forr types, (3) goethite-hostedelectrum, (4) electnrm cores, (5) electrumrims and (6) wire electrum,are associatedwith assemblagesof supergeneminerals in its oxidizedportions. Pyrite- hosted quartz-hostedand goethite-hostedelectrum range in compositionfrom 6l ta 75 utt.7oAu and have uniform textures and no zoning. In lower portions ofthe oxidized ore zone, electrum seemsto replacegoethite and occursas small grains on surfacesof the goethite.Textural evidencefavors supergeneremobilization of Au and Ag, which were depositedas electrum on or replacinggoethite. This type of electrumis identical in appearanceand compositionto prinary electrum,In the upper portions of the oxidized zone,secondary electum occursas a gold-rich rim on a core of elechum and as wire-like grains,both with acanthiteand uytenbogaardtite.Such secondaryelectrum contains from 78 to 93 wt./o Au. Textural relations and asso- ciated minerals suggestthat the primary electrum was hydrothermally depositedand partially remobilized by supergene processes.
    [Show full text]
  • THE JEWELRY of POTTERY MOUND with a Comparison To
    THE JEWELRY OF POTTERY MOUND With a Comparison to Tijeras Pueblo By Lucy C. Schuyler Maxwell Museum Technical Series No. 26 Maxwell Museum of Anthropology University of New Mexico 2016 TABLE OF CONTENTS Page LIST OF FIGURES......................................................................................................................... v LIST OF TABLES......................................................................................................................... vii ACKNOWLEDGMENTS.............................................................................................................. xi 1. INTRODUCTION....................................................................................................................... 1 Excavations at Pottery Mound............................................................................................. 2 Methods................................................................................................................................3 Overview of the Artifacts.....................................................................................................4 2. JEWELRY AND RELATED ARTIFACTS IN THE COLLECTIONS..................................... 5 Beads.................................................................................................................................... 6 Bone......................................................................................................................... 6 Shell........................................................................................................................
    [Show full text]
  • The Ag/Au Ratio of Native Gold and Electrum and the Geochemical Environment of Gold Vein Deposits in Japan
    Mineral. Deposita 22, 309-314 (1987) MINERALIUM DEPOSITA © Springer-Verlag 1987 The Ag/Au ratio of native gold and electrum and the geochemical environment of gold vein deposits in Japan N. Shikazono 1 and M. Shimizu 2 1 Geological Institute, Faculty of Science, University of Tokyo, Tokyo 113, Japan 2 Department of Petrology and Mineral Deposits, University Museum, University of Tokyo, Tokyo 113, Japan Abstract. The chemical composition of native gold and Yamaoka and Nedachi 1978; Shikazono 1985 a). Also, the electrum from auriferous vein and gold-silver vein de- geochemical environment (activity of 02 and $2, i.e., ao~ posits in Japan has been analyzed and summarized. The and ass, pH, total dissolved sulfur concentration, and Ag/Au ratios of native gold and electrum from these two temperature) of these deposits has been estimated (Shika- types of deposits are distinct, i.e., 10-20 Ag at % (auri- zono 1974, 1977a, 1978; Hattori 1975; Takeuchi and ferous vein) and 30-70 Ag at % (gold-silver vein). Thermo- Shikazono 1984). In contrast, few analytical data on native chemical calculations suggest that the Ag/Au ratio of gold and electrum from auriferous vein deposits are native gold and electrum should decrease with increasing available and the geochemical environment has not been chloride concentration and temperature. This is consistent elucidated except for the Kohoku deposit (Nedachi 1974). with analytical results of native gold and electrum and The objectives of this paper are to (1) present analyti- fluid inclusion studies. Based on the Ag content of native cal data on native gold and electrum from representative gold and electrum, the Fe content of sphalerite, and the auriferous vein deposits in Japan, (2) compare analytical estimated temperatures, it is deduced that the sulfur data on the native gold and electrum from auriferous veins activity for auriferous vein-type systems was lower than with those from gold-silver veins, and (3) discuss the that of gold-silver vein-type systems.
    [Show full text]
  • Artistar Jewels in Milan EXHIBITION / 19 FEB 2019 - 24 FEB 2019 Published: 12.12.2018
    Discover Art Jewelry from Selected Jewelers, Galleries and Institutions Artistar Jewels in Milan EXHIBITION / 19 FEB 2019 - 24 FEB 2019 Published: 12.12.2018 Bracelet and neckpiece made by Rachel Reilly. © By the author. Read Klimt02.net Copyright. Artistar Jewels, the international event dedicated to body ornaments now in its sixth edition, will be held for the first time at Palazzo Bovara in Corso di Porta Venezia in Milan. The entire building will be dedicated exclusively to the exhibition, with over 700 square meters of exhibition space. A not-to-be-missed opportunity to admire the beauty of contemporary jewellery declined in 500 sculptural ornaments, ironic, sometimes on the verge of wearability, inserted in an experiential path divided into themes: avant-garde, innovation, precious and recycling. The creations on show are of the highest artistic and technical level, most of which created for the project and never exhibited before. Artist list Hawraa Almaqseed, Nita Angeletti, Artifact Jewellery, Asimi, Aurum by Guðbjörg, Priyanka Baburaj, Francesco Barbato, Ronel Bauermeister, Miruna Belicovici, Raquel Bessudo, Glauco Cambi, Elizabeth Jane Campbell, Ana Margarida Carvalho, Milla Castro, Alva Chen, Valerie Cheung, Sarah Christian, Luana Loureiro Coelho, Marion Colasse, Anca Ioana Croitoru, Susan Crow, Silvia Cruceru, Sheila Cunha, Francesca Di Virgilio, Maria Elisabetta Donadio, Yichen Dong, Anastasia Dubrova, Dominika Durtan, Mikky Eger, Ellence, Quinta Essenza, John Farris, Mina Farrokhi, Flaminia Quattrocchi Design, Lindsey Fontijn,
    [Show full text]
  • MUMMIES BEYOND the GRAVE
    THE SOAP LADY USA, NORTH AMERICA MUMMIES BEYOND the GRAVE An Introduction to Mummy Studies around the World by janet monge RIGHT: Mummies are found throughout the world—in high mountains and low deserts, in both frigid and hot climates. The locations of the mummies discussed in the following INCA CHILD SACRIFICES articles are shown. PERU, SOUTH AMERICA ver 20 years ago, I got hooked on mummies. on mummy studies that give us both a view to the It began when we first x-rayed the many biology of peoples in the past as well as the cultural O South and North American mummies that circumstances that produce these unique artifacts of are part of the Physical Anthropology Section collec- human mortuary history. The articles in this special tions at the Penn Museum. This led to a drive to glean issue of Expedition illustrate the diversity of mummy even more information from the mummies. For several studies, the nature of mummification, and the cultural years, on Sunday mornings at 6 am, my students and I context of preserving the body. drove all the mummies of the collection one city block They also challenge us to consider questions like: to the Hospital of the University of Pennsylvania, what is a mummy? And what are the ethical concerns Department of Radiology, to CT scan and even MRI with manipulation, study, and display of these bod- them. Eventually we included the Egyptian Section ies? As both cultural and biological artifacts of past mummies, both human and animal. I am still hooked peoples, these authors bring together a diversity of
    [Show full text]
  • Archaeology Activity Book
    Archaeology Activity Book Illustrations: Heather Brindza Text: Danielle Ellis Layout: Rebecca Conway Appalachian Forest Heritage Area (AFHA) is a non-profit, grassroots organization that promotes economic and community development by linking central Appalachian forest history, culture, natural history, products and forest management into a multi-state heritage tourism initiative. Monongahela National Forest hosts AFHA-sponsored AmeriCorps service at forest sites that enhance natural resources and tourism and connect local communities. The Eastern National Forests Interpretive Association (ENFIA) is a non-profit association that aids and promotes the historical, scientific, and educational activities of the USDA Forest Service. This activity book was made possible through grants and partnership agreements with AFHA AmeriCorps, ENFIA, and USDA Forest Service. Archaeology is the study of material culture left behind by people from the past. Material culture are things created or used by people, like stone tools, a glass bottle, or even an entire building. Archaeologists look for archaeological sites to try to answer questions about the past. A site is where artifacts, features, or ecofacts are grouped together in an area. This means people were in that area in the past, and it’s up to the archaeologist to figure out what they were doing there. Sometimes archaeologists find things that can’t be easily collected or are part of the environment past peoples used. These things are called features. Features are often large, like the foundation of a house, or difficult to collect from the site, like an ashy campfire ring. Feature example: campfire ring Artifacts are things created or used by past peoples.
    [Show full text]
  • The Allopoiesis of the Artifact
    Syracuse University SURFACE School of Architecture Dissertations and Architecture Thesis Prep Theses 12-2015 The Allopoiesis of the Artifact Cristina Abondano Follow this and additional works at: https://surface.syr.edu/architecture_tpreps Part of the Architecture Commons Recommended Citation Abondano, Cristina, "The Allopoiesis of the Artifact" (2015). Architecture Thesis Prep. 276. https://surface.syr.edu/architecture_tpreps/276 This Thesis Prep is brought to you for free and open access by the School of Architecture Dissertations and Theses at SURFACE. It has been accepted for inclusion in Architecture Thesis Prep by an authorized administrator of SURFACE. For more information, please contact [email protected]. Cristina Abondano THE ALLOPOIESIS OF THE ARTIFACT (Of Pathological Permanence) Pathological Permanence image caption image caption Cristina Abondano THE ALLOPOIESIS OF THE ARTIFACT (Of Pathological Permanence) Cristina Abondano Advisor | Theodore L. Brown Secondary Advisors| Maya Alam, Daekwon Park 12 . 18 . 2015 Syracuse University School of Architecture The Allopoiesis of the Artifact image caption image caption 4 Cristina Abondano CONTENTS 7 Glosary 9 Claim 11 Proposal 13 Case Study | Castillo san Felipe de Barajas 23 The Urban Artifact In Crisis 27 Pathological Permanence 29 Death of the Political Idea 31 Interrupted Morphological Development 33 Un-Reciprocal Context 35 Physical Barriers of Context 43 Museification 45 -Poiesis 47 Autopoiesis 51 Allopathy 53 Allopoiesis 55 Euthanasia 57 Possible Program Needs 61 Thesis Publication
    [Show full text]
  • Archaeology for Kids!
    Archaeology For Kids! In this Issue: • Ask An Archaeologist • Archaeology Word Search • • Talk Like an Archaeologist • The Making of An Artifact • • Archaeology Scramble • Guess the Artifact • Ask An Archaeologist Do archaeologists dig up dinosaurs? Archaeologists study the material remains left behind by people in the past. They actually do not study dinosaurs and fossils, even though they may come across them by accident while they are digging. That’s when they call a palaeontologist, who study earth’s earliest inhabitants, like dinosaurs and early plants that are now extinct and preserved in layers of the earth as fossils. In the field, archaeologists and palaeontologists may look a lot alike because they use similar methods and sometimes similar tools to uncover the past. Palaeontology, however, teaches us about the history of the earth and its earliest inhabitants, while archaeology teaches us about ancient (and sometimes not-so-ancient) people. Do you have questions for one of our archaeologists? E-mail them to Archaeologist” along with your name and age [email protected] answer all your questions. Your question might even be featured in our next issue of with the subject line “Ask an Archaeology and we’ll be sure : For Kids! to Archaeology Word Search ANCIENT FORTS PYRAMIDS ARCHAEOLOGY HISTORIC RADIOCARBON ARTIFACT LONGHOUSE SITE CHERT MOUND SOIL DATING MUMMY STOCKADE EXCAVATE POTTERY TROWEL EXHIBIT PREHISTORIC Talk Like an Archaeologist Artifact: An object made or modified by humans. Some artifacts are stone tools, pottery, jewelry, and clothing. Archaeologists often find artifacts of pottery, glass, or stone, which last longer in the ground than fabric or leather.
    [Show full text]
  • Selective Brush Plating for Decorative Applications
    SELECTIVE BR USH PLATING FOR DECOJ$ATIVE AP PLICATIONS Jeff Hurrell Brooktronics Engineering Corp. 13161-B Sherman Way North Hollywood, CA 91605 Abstract The selective brush plating process is generally known as a selective metal deposition process for industrial or aerospace applications. However, the brush plating process has been successful in producing decorative finishes for a vast array of decorative finishing applications. Special techniques have been used to produce attractive, high quality decorative .finishes in many instances were conventional bath plating would be impossible or too costly. Also, additional finishes have been developed for use with brush plating, such as a patented, corrosion resistent, brass colored finish. ,Introduction For many years, conventional tank plating has been invaluable for the decorative finishing of metal and plastic parts. Through the extensive use of decorative plating, applications for brush plating have become significant in the decorative finishing industry. The versatility of brush plating has played an important role in the growth of decorative brush plating. This paper will explore brush plating as a processing technique for decorative finishing. Areas of discussion will include an explanation of brush plating, various applications, finishes available, processing techniques including the limitations of the process, and future developments in brush plating for decorative finishing. The Brush Platina Process The brush plating process is an electrodeposition process by which metal, pure or alloy, is selectively deposited on only the specific area which requires electroplating. The brush plating process can be used as a portable system or a fixed installation (see Figure 1). The equipment and solutions for brush plating are capable of producing high quality deposits, although brush plating systems are relatively inexpensive.
    [Show full text]