C05_P02

Barley Mash its history in the Radiocarbon Inter-comparison studies and its role as a modern carbon standard.

Naysmith P¹, Scott M², Dunbar E¹

¹SUERC, East Kilbride, United Kingdom, ²School of Mathematics and Statistics, University of Glasgow,

Over the past 30 years, the format of the radiocarbon (¹⁴C) inter-comparison studies has changed due to the change and development in measurement techniques. The selection of sample types used in these studies has remained constant—namely, natural and routinely dated materials that could subsequently be used as in-house laboratory standard material. Barley Mash, a by-product from the manufacture of malt whisky, is a good example of one of the widely used material from the Intercomparison studies.  Barley from a single year’s growing season is used in the production of whisky, often coming from a single geographical location and is available is large quantities, thus making it a suitable modern carbon reference material. Barley Mash samples have been used ten times in inter-comparison starting with TIRI, in 1992 through to GIRI, in 2021, with the same batch of barley mash being used in multiple inter-comparison studies. In this paper, the barley mash results from all the intercomparisons will be collated and reanalysed.

During the last 19 years, the Barley Mash TIRI A has been used in the SUERC ¹⁴C laboratory as an in-house laboratory standard material resulting in a dataset of several thousand of measurements. Such a rich data set is mined to illustrate some of the benefits arising from the inter-comparison program.