Pre-hispanic goldwork in the British Museum: some recent technological studies

Un examen tecnológico de orfebrería prehispánica suramericana de la colección del Museo Británico está llevándose a cabo actualmente. Usando microanálisis y microscopía electrónica de barrido se ha identificado una variedad de aleaciones y de técnicas de metalurgia antiguas usadas para producir un amplio rango de artefactos de oro. En este artículo se ilustra la investigación detallada de algunas fases binarias y de fundiciones ricas en cobre con superficies doradas. El análisis de anzuelos del río Cauca muestra el uso de un rango amplio de composiciones de aleaciones, desde oro argentífero aluvial hasta aleaciones de oro con alto contenido de cobre, tanto para alambres martillados como para artefactos fundidos. Se examinan en detalle, igualmente, las marcas dejadas por las herramientas sobre los objetos de oro

Glassy Microspherules from Bomb Combustion of Charcoal

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

British Museum Natural Radiocarbon Measurements VI

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Precision Lost Wax Casting

The limits of precision casting were explored experimentally at the Bronze Casting Workshop at Wilhelminaoord, the Netherlands, by making wax models, moulds and lost wax castings using essentially early metalworking conditions. Geometrically patterned models of Dark Age type dies were used to make wax patterns to simulate one of the finest detailed objects to come from excavation, the Tjitsma die. Examination of mould surfaces and castings by scanning electron microscopy showed that the limiting surface resolution of lost wax casting in bronze was the finely textured dendritic cast surface. The mould surfaces had taken the geometric pattern of the original wax models very well, although there is a fine particulate texture to the mould surface, but this is far finer than the limiting dendritic surfaces of the cast bronze

British Museum Natural Radiocarbon Measurements VIII

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

British Museum Natural Radiocarbon Measurements IX

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

British Museum Natural Radiocarbon Measurements VII

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Technological characterisation of egyptian blue

The principal aim has been to obtain information on the procedures used in antiquity to produce the different fabrics, ranging from soft and friable to hard and semi-vitrified, which are composed of Egyptian Blue. Four pieces of Egyptian Blue from Egypt and Mesopotamia have been examined using the scanning electron microscope and have been compared with Egyptian Blue produced in the laboratory. The results show that Egyptian Blue can be satisfactorily synthesized by firing an appropriate mixture to 900-1000°C for a few hours and to produce pieces comparable in hardness and microstructure with the ancient samples, a single firing in this temperature range is sufficient for the softer fabrics. However, to produce the harder fabrics it is necessary to fire for a second time after grinding and remoulding the material from the first firing.L'objectif principal a été d'obtenir des informations sur les procédés employés dans l'antiquité pour produire les différentes pâtes, allant du tendre et friable au dur et semi-vitrifié, qui sont composées de Bleu Egyptien. Quatre objets de Bleu Egyptien d'Egypte et de Mésopotamie ont été examinés au microscope électronique à balayage et ont été comparés avec du Bleu Egyptien produit au laboratoire. Les résultats montrent que le Bleu Egyptien peut être synthétisé de manière satisfaisante en chauffant un mélange approprié à 900-1000°C pour quelques heures et qu'on peut produire des pièces comparables en dureté et en microstructure avec les échantillons antiques, une seule chauffe dans cette gamme de température est suffisante pour les pâtes tendres. Cependant, pour produire les pâtes les plus dures il est nécessaire de chauffer une deuxième fois après avoir broyé et remodelé le produit du premier chauffage.Tite Michael S., Bimson Mavis, Meeks Nigel D. Technological characterisation of egyptian blue. In: Revue d'Archéométrie, n°1, 1981. Actes du XXe symposium international d'archéométrie Paris 26-29 mars 1980 Volume III. pp. 297-301