Pierandrea Malfi

Multi-parametric micro-mechanical dating of single fibers coming from ancient flax textiles

A new micro-mechanical method for textiles dating was applied to flax fabrics. Notwithstanding that environmental factors like temperature and humidity can influence the mechanical parameters of ancient textiles, the method shows a relatively stable trend if some previous analysis is done to eliminate degraded samples. This method is based on a multi-parametric analysis of single fibers tested on a proper machine designed and calibrated for the purpose. Single fibers mounted on special supports are submitted to mechanical test consisting of multiple stress–strain cycles. The parameters sensitive to aging are tensile strength, Young modulus, and loss factor, the last two evaluated during particular phases of loading cycles. Five different calibration curves relating age to these mechanical parameters are determined by using a series of eleven textiles of known age from 3250 BC to 2000 AD that passed a proper pre-selection. The resulting age of the textiles derives from a combination of five independent dating. The relatively small number of textiles used for the analysis, due to the fact that it is not easy to find ancient textiles, gave results that can be improved by future analyses addressed to test a larger number of samples. For the moment, the relative standard uncertainty of the method is about 200 years but future test could reduce this uncertainty. This relatively simple method can also be useful to museums which wish to date themselves ancient textiles at low cost.