Dating iron bloom

Sayre, E. V., Harbottle, G., Stoenner, R. W., Washburn, W., Olin, S., Fitzhugh, W., The Carbon 14 Dating of ao Iron Bloom Associated with the Voyages of Sir Martin Frobisher, Chapter 22 in this book. 

The Carbon-14 Dating of an Iron Bloom Associated with the Voyages of Sir Martin Frobisher... 

Development of proportional counters to measure C14/C12 ratios in 10 mg carbon samples was undertaken in the Chemistry Department of Brookhaven National Laboratory in 1975 [10] for two reasons (1) at the time, there was no other possibility in sight to accomplish the generally much-needed objective of small-sample C14 measurement, and (2) there was a particular carbon 14 dating problem at the Smithsonian Institution, which would only be solved if very small carbon samples could be handled. The development and testing of the counters has already been reported [9] in the present paper we discuss the application of those counters to the actual dating problem which concerned the Smithsonian Institution, the dating of the "Frobisher iron bloom". 

Bloomery iron is characterized, however, by very low carbon content (Table 1) and if one wished to carry out a conventional carbon 14 dating, consumption of the entire 20 lb. bloom would have yielded only 4 or 5 grams of carbon, which is barely enough. For this reason, the Conservation-Analytical Laboratory of the Smithsonian Institution sponsored the development of the micro-scale dating procedures at Brookhaven Laboratory already referred to above [9,10]. 

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