Tracing the Source of the Elephant And Hippopotamus Ivory from ...

perpendicular to the tubules....[collagen is] found as a meshwork between the dentinal
tubules” (Turner et al. 2000: 71).
Raubenheimer et al. (1998) conducted analyses of the inorganic and organic
content of elephant ivory from seven park reserves in South Africa, Botswana, and
Namibia. They were able to detect 20 elements in the inorganic fraction, and showed
statistically significant differences in some of the elemental concentrations between
different regions. Nevertheless, such analyses are not practical for the purposes of this
thesis, as they require a very large dataset of elephant ivory from known and bounded
geographical locations.
The researchers also found in their analyses of the organic fraction that the ivory
from arid regions had significantly lower proline and hydroxyproline content and under-
hydroxylation of lysine residues. Thus ivory from Kaokoveld and Etosha are more brittle
and hydrolyzed more rapidly than the ivory from other regions (Raubenheimer et al.
1998: 641-643; Raubenheimer 1999: 62). Both the Kaokoveld and parts of Etosha have
less than 200 mm rainfall per annum, and the elephants inhabiting these regions, known
as “desert” elephants, will be discussed in Chapter Eight (see Viljoen 1988). The
strength of collagen would be affected by malnutrition, and in particular a vitamin C
deficiency. Kaokoveld and Etosha ivory also have high flouride contents, which
effectively softens the mineral fraction and weakens the crystal (Raubenheimer et al.
1998: 645-646). All the same, hardness, and by extension ‘brittleness,’ is not
acknowledged as an accurate criterion to consider in provenancing ivory, and at any rate,
would be exceedingly difficult to demonstrate as feasible for ancient ivory due to
differential preservation and diagenetic processes.
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