Piero sends from Italy some useful links and opines that “this is not the right way to discover something about the linen fibrils of the Holy Shroud.”:
I have found a reference : “Strontium Isotopic Tracing of Bronze Age Danish Textiles” and you can read under the address : http://ctr.hum.ku.dk/tecc/strontium/ the following words :
>One of the most important questions that archaeologists pose to ancient material is the question of origin. However, provenance is one of the hardest pieces of information to obtain about any archaeological object in absolute terms. Recently the development of a new archaeometric tool which enables to gather information on the provenance of ancient textiles raw material, created a new important possible source of information within the field of textile research.
> This tracing method rests on the fact that each geological area has a characteristic strontium isotopic ‘signature’, which is transferred to plants and animals without fractionating throughout the food chain. Thus these signatures are also transferred to the wool or plant fibres of textiles. Moreover, by developing baselines of the bio-available strontium isotope ratios of the retrieval site it is possible to establish if the raw material (wool/plant fibre) is of local provenance or not.
> This method is applicable also to dyed material. …
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So …
Which is the inherent precision level ?
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under : http://www.springerlink.com/content/l16071lk20433r42/ I have found another reference : Strontium isotopes and human mobility in prehistoric Denmark Karin Margarita Frei and T. Douglas Price
Abstract
>The principles behind the strontium isotopic system are an important tool for archaeologists tracing human migration and patterns of movement in prehistory. However, there are several scientific challenges of analytical nature, as well as those which relate to unknown parameters inherent to the interpretation of such data. One prerequisite is the knowledge of the range of strontium isotopic ratios that best characterize the bioavailable fractions of a particular area of interest. The study reported here attempts to establish a baseline for strontium isotope signatures valuable for Denmark (excluding the island of Bornholm) and particularly for the use in archaeological investigations. We present strontium isotope ratios of bones and teeth from modern mice contained in owl pellets, of snail shells, and of archaeological fauna samples. We compare these ratios with median strontium isotope signatures characterizing human enamel populations from archaeological sites within Denmark. The fauna samples reportedhere range from 87Sr/86Sr = 0.70717 to 0.71185 with an average of 0.70919, and human enamel defines a range from 87Sr/86Sr = 0.7086 to 0.7110 with an average of 0.7098. In both datasets, we observe a small difference between the baseline values for the western (Jutland) and eastern (Funen, Zealand, and the southern islands) parts of Denmark. We therefore propose two slightly different baseline ranges with a partial overlap for the isotopic signatures of bioavailable strontium fractions within Denmark, namely a range of 87Sr/86Sr = 0.7078–0.7098 for the western area and a range of 87Sr/86Sr = 0.7089–0.7108 for the eastern parts.
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What is the possibility to work with the fibrils coming from the Shroud ?
In my opinion this is not the right way to discover something about the linen fibrils of the Holy Shroud.
What is your remark ?
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Best regards,
Piero
I disagree. I don´t want to repeat myselfbut although strontium by itself migh not be conclusive, in combination with other trace elements (1)(2) may allow identification of textiles’s geographical origin.
(1)Takako Inoue, Kengo Ishihara and Kyoden Yasumoto.International Journal of Clothing Science and Technology Vol. 22 No. 2/3, 2010 pp. 174-186
(2) Emily R. Schenk and Jose R. Almirall. Elemental analysis of cotton by laser-induced breakdown spectroscopy. May 2010 / Vol. 49, No. 13 / APPLIED OPTICS
Much of the Danish work seems to have been done by Karin Margarita Frei (connections with Max Frei?? – just speculating). My chemistry is limited, but I note that altho’ 87Sr and 86Sr are both stable isotopes themselves, the amount of 87Sr has been increasing over time because it is also a decay product of 87Rb, and this is said to be evident in meteorites. Is there a possibility that this may compromise its value as a provenance indicator of ancient textiles? Thus we may know the 87/86Sr ratios of an ancient textile, which may have remained unchanged over time, but is it valid to compare this with a present geographic / geologic region if the ratio in that regions may have changed because of decay of 87Rb? Can anyone elucidate? If this is a potential problem, would it not then be valid to compare textiles of comparitive ages if the provenance of any one of them were known? Or is this a false problem?