Provenance studies of British prehistoric greenstone implements using non-destructive analytical methods
Geochemical data obtained using field-portable non-destructive X-ray fluorescence instrumentation (PXRF), supported by magnetic susceptibility (MS) measurements, is able to narrow the provenance of IPC Group I prehistoric greenstone axes to two locations in West Cornwall: St Ives and Mullion Island. It also supports the provenance of IPC Group III axes to a greenstone quarry near Perranuthnoe, Cornwall and supports the Cornish origin of seven Irish gabbroic and doleritic axes. Provenancing methodology involved the examination of 149 axe and 73 greenstone thin sections, followed by comparison of 272 axe and over 100 exposure geochemical and magnetic analyses using Simple Component Analysis (SCA), element discrimination diagrams, Discriminant Analysis (DA) and comparative statistics (MANOVA, West). Accuracy, precision and detection limits of the PXRF are determined using international reference samples, greenstone samples and greenstone axes. PXRF instrumentation is generally linearly calibrated with zero offset, and with a compensatable bias for K, Ca, Ti, Mn, Fe, Rb, Sr, Y, Zr, Nb, Ba, Ce and Pb. Precision in measuring greenstone rock composition is 5.3% relative standard deviation of the mean based on two
Markham, Michael
Cornish; Axe factories; Petrology
Provenance studies of British prehistoric greenstone implements using non-destructive analytical methods. Geochemical data obtained using field-portable non-destructive X-ray fluorescence instrumentation (PXRF), supported by magnetic susceptibility (MS) measurements, is able to narrow the provenance of IPC Group I prehistoric greenstone axes to two locations in West Cornwall: St Ives and Mullion Island. It also supports the provenance of IPC Group III axes to a greenstone quarry near Perranuthnoe, Cornwall and supports the Cornish origin of seven Irish gabbroic and doleritic axes. Provenancing methodology involved the examination of 149 axe and 73 greenstone thin sections, followed by comparison of 272 axe and over 100 exposure geochemical and magnetic analyses using Simple Component Analysis (SCA), element discrimination diagrams, Discriminant Analysis (DA) and comparative statistics (MANOVA, West). Accuracy, precision and detection limits of the PXRF are determined using international reference samples, greenstone samples and greenstone axes. PXRF instrumentation is generally linearly calibrated with zero offset, and with a compensatable bias for K, Ca, Ti, Mn, Fe, Rb, Sr, Y, Zr, Nb, Ba, Ce and Pb. Precision in measuring greenstone rock composition is 5.3% relative standard deviation of the mean based on two
provenance study british prehistoric implement use non_destructive analytical_method geochemical data_obtain use field portable non_destructive x_ray_fluorescence pxrf support magnetic_susceptibility measurement able narrow provenance group prehistoric location west cornwall island also support provenance group iii axes quarry near cornwall support cornish origin irish provenancing involve examination axe thin_section follow comparison axe exposure geochemical magnetic analysis use simple component analysis element discrimination diagram discriminant analysis comparative statistic west accuracy precision detection limit pxrf determine use international reference sample sample pxrf generally zero offset bias precision measure rock composition relative standard deviation mean base