Archaeologia Islandica - 01.01.2009, Síða 49

Geochemical Identification of Obsidian Artifacts
Trace Elements
Cat. No. Rb Sr Y Zr Nb Ba Chemical Tvne
NI-3532 80 130 94 895 116 662 Katla
(This analysis) ±4 ±3 ±4 ±4 ±3 ±18
NI-3532 (Jónasson 2007)a, 78 128 96 1004 114 726 Katla
NI-21680 64 63 162 362 82 459 Hágöngur
(This analysis) ±4 ±3 ±4 ±4 ±3 ±18
NI-21680 (Jónasson, unpublished data) 64 67 183 404 97 518 Hágöngur
NI-21702 123 15 118 1135 164 161 Torfajökull
(This analysis) ±4 ±3 ±4 ±4 ±3 ±18
NI-21702 (Jónasson 2007)a 123 14 133 1270 166 187 Torfajökull
NI-21839 86 64 117 477 135 787 Kerlingarfjöll
(This analysis) ±4 ±3 ±4 ±4 ±3 ±18
NI-21839 (Jónasson 2007)a 83 64 121 537 143 855 Kerlingarfjöll
NI-24189b 62 97 99 497 56 537 Krafla
(This analysis) ±4 ±3 ±3 ±4 ±3 ±14
NI-21969 (Jónasson 2007) 77 91 111 441 52 590 Krafla
Sample # 14 (Jónasson 1994: Table 3) 66 97 98 475 52 524 Krafla
Note: a, Comparative data from Jónasson (1994: Table 3; 2007: Tablel) rounded to the nearest
ppm. b, At the time of this writing Jónasson had no measurements on Krafla sample NI-24189,
but he wrote to the senior author that data published for sample NI-21969 from Krafla should
represent the same composition as NI-24189 (Jónasson, personal communication). Katla chemical
type sampled from Kriki; Kerlingarfjöll sampled from Ogmundur; Torfajökull sampled at
Hrafntinnusker; Krafla samples represent the third phase of rhyolite volcanism; NI-21969 sampled
from Hlíðarfjall.
Table 3. Comparison of Trace Element Concentration Measurements for Five Icelandic
Obsidians
Laboratory Analysis
Non-destructive energy dispersive x-ray
fluorescence (edxrf) analysis of the four
Hofstaðir obsidian artifacts was con-
ducted by the senior author using a
QuanX-EC™ (Thermo Electron
Corporation) edxrf spectrometerequipped
with a silver (Ag) x-ray tube, a 50 kV
x-ray generator, digital pulse processor
with automated energy calibration, and a
Peltier cooled solid state detector with
145 eV resolution (FWHM) at 5.9 keV.
The x-ray tube was operated at differing
voltage and current settings to optimize
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