Bronze age relics and cricket
The Queensland ACA branch hosted Ian McLeod on the 9th November 2017 at the home of Queensland Cricket – the “Gabba.”
Ian’s animated style drew a roomful of corrosionists and supporters to hear a fascinating tale of his recent scientific discoveries on a bronze age archaeological site in Turkey.
Ian explained the diverse corrosion mechanisms of bronze, the material of choice for all things containing, fastening and artistic 3500 years ago. Despite its non-ferrous nature, bronze will corrode in the right environment. These ions flowing through the soil and varying oxygen levels have an effect on the pace of bronze corrosion. Bacteria too, producing acidic metabolites from produced nitrates contribute to the breakdown of the bronze artefacts.
Ian’s discoveries included noticing that corrosion mechanisms change with the depth of the soil. As usual, the story around the science is in itself a discovery, for instance, Ian discovered that working with the Japanese site management required a 5:15 am breakfast, a 9:15 breakfast and a 6 day a week working regime amongst other idiosyncrasies.
Ian also the discovered the “bum soil moisture test.” This test involves sitting in a place for long enough such that the soil moisture was felt on the…er skin. The length of time this took was the measurement indicating the wetness of the soil and hence an electrolytic soil measurement was possible (for corrosion measurement purposes).
No talk of Ian’s is complete without some maritime history, and the audience was not disappointed. Two shipwreck corrosion cases on Roly Shoals were examined.
We look forward to making this talk an annual event and encourage ACA members to attend Ian’s talks not only for the fascinating scientific explanations but the way they are explained.