A magnetic study of Etruscan bucchero pottery: An application of rock magnetism to archaeometry

Abstract

We have applied techniques used in rock magnetism to the study of possible temporal changes in provenance and firing conditions of a collection of Etruscan bucchero pottery fragments representing the interval between 800 B.C. to 400 B.C. To our knowledge, this is the first time that such procedures have been applied to ancient ceramic wares. Our preliminary magnetic measurements demonstrate that this approach can provide useful archaeological information, as exemplified by the following results: ( 1 ) Bucchero ceramic styles sottile, spesso, and possibly pesnnte, contained magnetic particles of similar grain sizes, which suggested a common provenance and similar firing conditions for these pot typologies. (2) Ceramic styles buccheroid impasto and grey bucchero each had magnetic characteristics different from those in ( 1 ) . However, too few samples of these were available for any definite conclusions. Most magnetic techniques are fast, easy, and generally nondestructive. Some magnetic properties, such as initial susceptibility, saturation remanent magnetization, and coercivity of remanence, can even be measured in the field. At the least, magnetic measurements can be used initially to discriminate among different groups of potsherds. Selected samples can then be analyzed with more elaborate methods of archaeometry.

Solving archaeological problems using techniques of soil magnetism

“…Other archaeological applications include: (1) archaeomagnetic dating, where measurements of past geomagnetic declination and inclination are used to date oriented features, artifacts, or deposits (Eighmy and Sternberg, 1990); (2) materials analysis, where magnetic studies are used to comprehend technologies or source materials such as coins, ceramics, obsidian, etc. (Kostikas et al, 1974;Chevalier et al, 1976;Gangas et al, 1976;Evans, 1977;Tanner et al, 1979;Tarling, 1982Tarling, , 1983Hoye, 1983;McDougall et al, 1983;Schmidbauer et al, 1986;Goulpeau et al, 1987;Moskowitz et al, 1987;Borradaile et al, 1998, this issue); and (3) mineral magnetic studies of lake or bog cores, generally in conjunction with pollen and other analyses, to document changes in human land use, climate, or fire frequency. In these lakebased studies, mineral magnetic characterizations are used frequently to identify increased erosion resulting from the inception of agricultural activity (Oldfield et al, 1983;Thompson and Oldfield, 1986;Almgren, 1989;Dearing et al, 1990;Ollendorf, 1993;Lagerå s and Sandgren, 1994).…”

ARCHAEOMAGNETISM IN ARCHAEOMETRY— A SEMI‐CENTENNIAL REVIEW*

“…Other monuments showed variations in susceptibility during different construction phases, which presumably reflected reliance on different sources. Susceptibility and other magnetic properties have also been measured for ceramics (Moskowitz et al 1987), obsidians (McDougall et al 1983), cherts (Thacker and Ellwood 2002) and ochres (Mooney et al 2003) to consider questions of provenance and technology.…”

Magnetic Alteration of Soils by Late Holocene Hunter–Gatherer Groups (Tierra Del Fuego, South America)

“…Dalan and Banerjee () and Dalan () exhaustively revised the broad applicability of magnetic properties in archaeological contexts, which can be summarized as follows: Magnetic properties as the definition of activity areas, functionality, building strategies, pigment sources and intensity of human occupation (e.g., Oldfield et al ; Allen and Macphail ; Clark ; Dockrill and Simpson ; Gose et al ; Crowther and Barker ; Dalan ; Marmet et al ; Orgeira et al ; Crowther ; Mooney et al ; Goldberg and Macphail ; Macphail and Crowther ; Rosendahl et al ; Ozán and Orgeira ; Tsatskin and Gendler ). Magnetic properties as chronological frames. In archaeological stratigraphies, palaeomagnetism can be used as a chronological indicator due to the presence of a known aged magnetic feature (e.g., Evans ; Tarling ; Schmidbauer et al ; Moskowitz et al ; Eighmy and Sternberg ; Nami ; Chiari and Lanza ; Borradaile et al ; Ellwood et al ). Magnetic proxies for pedogenetic, geomorphological dynamic, natural fire occurrence and post‐depositional processes. As upper soil horizons and surfaces affected by fire may have a distinctive magnetic signal, magnetic studies are palaeoenvironmental proxies.…”

“…(2) Magnetic properties as chronological frames. In archaeological stratigraphies, palaeomagnetism can be used as a chronological indicator due to the presence of a known aged magnetic feature (e.g., Evans 1977;Tarling 1983;Schmidbauer et al 1986;Moskowitz et al 1987;Eighmy and Sternberg 1990;Nami 1995;Chiari and Lanza 1997;Borradaile et al 1998;Ellwood et al 2004). (3) Magnetic proxies for pedogenetic, geomorphological dynamic, natural fire occurrence and post-depositional processes.…”