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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Raman spectroscopic studies of the underglaze pigments of porcelain shards of archaeological origins

Kock, L.D. (Lesotlho David) 06 June 2010 (has links)
The technique of Raman spectroscopy was used in a study of shards of known (Ming and Meissen) and unknown (archaeological) origin. A tile shard from the Citadel of Algiers was included in this study as further confirmation of the consistency of the methods that are developed. The Citadel from which the tile shard was obtained was built in 1516 and represents a landmark from pre-colonial Algeria. The results were compared with those obtained from studies on intact museum pieces of known (Ming) origin. A consistent method of studying underglaze pigments on glazed ceramic artifacts by directing the laser beam through the predominantly silicate glaze was developed. The glaze depth profiling method developed proved to be very useful in the analysis and gives not only a detailed composition for the glaze/ceramic interfacial pigment, but also the order in which the various interfacial pigment layers were applied at the time of manufacture. The information acquired leads to an understanding of the level of technological development of the manufacturers. The detailed study and characterisation of the pigments that were analysed in this way gives insight into trade relations among ancient societies of the Mediterranean and will also assist archaeologists in establishing cut-off dates for the archaeological sites from which the artifacts were recovered. All the shards, except one from Meissen (Germany), were provided by the National Cultural History Museum of South Africa and the intact Ming dynasty plates were provided by the J.A. van Tilburg Museum of the University of Pretoria. The tile shard sample from the Citadel of Algiers was donated for the study. The results indicate that none of the archaeological shards could possibly be of Ming dynasty origin based on, firstly, the use of amorphous carbon to darken the cobalt blue (CoAl2O4) used as decoration on the shards, and secondly on the use of white (synthetic) anatase to whiten the ceramic surface before the application of the pigment since this synthetic anatase is known to have been manufactured for the first time around 1920. An ancient rediscovered ternary pigment (Pb2SnSbO6.5) previously found on Italian paintings of the 16th century, for example, “Lot and his daughters” by G.B. Langetti and “Entrance of Christ in Jerusalem” by Luca Giordano, was identified on the Citadel tile and successfully characterised. A Pb-O vibrational Raman band at 127 cm-1 for this pigment was assigned for the first time. Additional pigments identified on the tile include Naples yellow (Pb2Sb2O7), lead (II) stannate (Pb2SnO4), cobalt blue (CoAl2O4) and cassiterite (SnO2). The bulk of the tile body is composed mainly of hematite (á-Fe2O3), maghemite (ã-Fe2O3), magnetite (Fe3O4) and quartz (á-SiO2), with traces of calcite (CaCO3) and amorphous carbon. The unique non destructive depth profiling method that was developed in this study can now be applied to the study of underglaze pigments on intact porcelain artifacts in museums and private collections around the world for authentication purposes and for comparison with archaeological shard samples. / Thesis (PhD)--University of Pretoria, 2010. / Chemistry / unrestricted
2

Geoarqueologia dos sítios pontão e Santa Helena na região de Silves-AM

Santana, Rafaela Ferreira de, 92-98196-7677 09 May 2018 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-08-22T12:49:12Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_RafaelaSantana.2018.pdf: 10128840 bytes, checksum: 442134efbb618d4c2b83d92da2fdf8a2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-08-22T12:49:39Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_RafaelaSantana.2018.pdf: 10128840 bytes, checksum: 442134efbb618d4c2b83d92da2fdf8a2 (MD5) / Made available in DSpace on 2018-08-22T12:49:39Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_RafaelaSantana.2018.pdf: 10128840 bytes, checksum: 442134efbb618d4c2b83d92da2fdf8a2 (MD5) Previous issue date: 2018-05-09 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This article provide a Geoarchaeological contribution for the study of the settlement of the Pontão (AM-SL-06) and Santa Helena (AM-SL-07) archeological sites located in the Lower Urubu River, in the township of Silves, Amazonas. The objective is analyze the deposition system of the archaeological vestiges and characterizing the black earth of indian and ceramic artifacts related to these sites. The methodology process adopted is based on a morphological, mineralogical and chemical analysis of soil samples, sediments and ceramic traces. The soils of the region are classified as immature profiles, formed on Alter do Chao formation, the mineralogy is represented by quartz, kaolinite, hematite, gibbsite and goethite, the sediments come from alluvial deposits that constitute a clay-sandy material, mineralogically composed by 2: 1 clay, quartz and iron oxides. The black soil can reach 40 to 220 cm depth, with a sandy granulometry for Pontão site and a sandy-clay for Santa Helena site, consisting of quartz and kaolinite and high proportions of Ti, Zr, Ag and Mn. Ceramics artifacts are commonly associated as pre colonial period: Incisal Edge Tradition an the Saracá regional Tradition, being mineralogically constituted by quartz, kaolinite, smithite, illite, gibbsite, hematite, feldspar, phosphates, and presents additional seasonings to the blend of cauixi, cariape and ceramics shards, which are distinguished only by the proportion of this constituents for each of the studied sites. Based on the analyzes of ceramic data is possible to infer two places as being the material provider: the first, associated to the immature profiles is formed on the cretaceous deposits and the second, associated to the sediments is coming from the alluvial deposits present in the lakes of the region, which currently provides primary resources for the manufacture of tiles and bricks. For questioning about the origin of the resource areas and manufacturing of the artifacts from the studied sites, we can correlate that the ceramics were produced locally with the raw material available in the region. / Este trabalho apresenta as contribuições da Geoarqueologia no estudo sobre o assentamento dos sítios arqueológicos Pontão (AM-SL-06) e Santa Helena (AM-SL-07), localizados na região do baixo rio Urubu, no município de Silves, Amazonas. O objetivo está em analisar o ambiente de deposição dos vestígios arqueológicos e caracterizar a terra preta de índio e artefatos cerâmicos relacionados a estes sítios. A metodologia adota está na analises morfológica, mineralógica e química das amostras de solos, sedimentos e vestígios cerâmicos. Os solos da região são classificados como perfis imaturos, formados sobre a Formação Alter do chão, com mineralogia representada por quartzo, caulinita, hematita, gibbsita e goethita, os sedimentos são provenientes dos Depósitos Aluvionares que constituem um material argilo-arenoso, compostos mineralogicamente por argilominerais do tipo 2:1, quartzo e óxidos de ferro. A terra preta nestes sítios alcança profundidades entre 40 a 220 cm, com granulometria arenosa para o Sítio Pontão e argilo-arenosa para o Sítio Santa Helena, constituídas por quartzo e caulinita e proporções altas de Ti, Zr, Ag e Mn. Os artefatos cerâmicos são associados as fases cerâmicas pré-coloniais: Tradição Borda Incisa e a Tradição Regional Saracá, sendo constituídas mineralogicamente por quartzo, caulinita, esmectitas, illita, gibbsita, hematita, feldspatos, fosfatos e apresentam temperos adicionados a sua mistura de cauixi, cariapé e cacos cerâmicos, sendo diferenciados apenas pelas proporções destes constituintes para cada um dos sítios estudados. Com base nas análises feitas é possível atribuir dois lugares como áreas de proveniência de matéria prima desses artefatos cerâmicos: o primeiro, associado aos perfis de solos imaturos formados sobre os depósitos cretáceos e o segundo, associado aos sedimentos provenientes dos depósitos aluvionares presentes nos lagos da região, que atualmente constituem depósitos de matéria prima para a fabricação de telhas e tijolos. Para questionamentos sobre áreas fontes e fabricação destes artefatos dos sítios estudados, podemos correlacionar que as cerâmicas foram produzidas localmente com a matéria prima disponível na região.

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