Varmuza K.*, Werther W., Sauter F.
Poster Presentation
ICAS 2001: IUPAC
3rd International Congress on Analytical Sciences
6 - 10 August 2001, Waseda
University, Tokyo, Japan
In
1991 the frozen mummy of a more than 5000 years old man was found in South
Tyrol (Italy) near the frontier to Austria. On the weapons aside this
"Tyrolean Iceman" traces of a dark organic material were detected - a
pitch, obviously used to fix the arrowheads as well as the blade of the hatches
to their shafts. Aim of the presented work was to find out from which species
of trees this pitch had been prepared, and in particular to show whether or not
it is pitch prepared from the birch tree - the same material as was found
earlier in coatings on prehistoric pottery.
Best
results were achieved by comparing the significant triterpene fraction of the
prehistoric samples with those of model pitches prepared from wood and/or bark
of a variety of trees. The characteristic fractions were cut out by
distillation under reduced pressure, followed by solid phase extraction.
The
comparison of the various triterpene fractions obtained was achieved by GC/MS,
followed by multivariate data interpretation. Application of principal
component analysis and partial least squares discriminant analysis showed that
the pitch from the Tyrolean Iceman was prepared by pyrolysis of bark taken from
the birch tree (Betula verrucosa).