Charcoal and vegetation sample (Blankenship, 1970)

About This Sample

Charcoal embedded in a large piece of decayed vegetation, recovered from Oak Island in October 1970 by Dan Blankenship, the Triton Alliance field manager who led the Smith's Cove excavations of 1969 and 1970. Two fractions of this composite sample were dated separately: • Charcoal fraction (Brock University, BGS-26): 2040 ±58 years before present → approximately 90 BC, with a range of 148-32 BC. • Decayed vegetation - cones and plant detritus (Brock University, BGS-26B): 1660 ±82 years before present → approximately 290 AD, with a range of 208-372 AD. The charcoal represents some of the oldest datable organic material recovered from Oak Island, pre-dating the Common Era by over a century. The approximately 380-year age difference between the charcoal and the surrounding vegetation likely reflects different depositional events or the inherent characteristics of charcoal preservation versus vegetative decay. Dan Blankenship sent this sample to Dr. Jan Terasmae at Brock University along with three other specimens on 16 October 1970. In his accompanying letter, Blankenship described the sample as "a piece of charcoal still imbedded in a large piece of decayed vegetation (called coconut fibre)" and recommended both the charcoal and vegetation for C14 dating, noting that charcoal is considered a reliable material for radiocarbon analysis. Dr. Terasmae reported the results to Kerry Ellard on 24 December 1970, noting that he had dated two fractions of the charcoal and plant matter sample. He confirmed the charcoal date at 2040 ±58 BP and the cones/detritus at 1660 ±82 BP. There was not enough of the suspected coconut fibre in the sample for separate dating. Terasmae also identified a nearby plank (Item #2 on the Smith's Cove Grid Plan) as eastern hemlock with a reasonably sensitive tree-ring record, suggesting it might be possible to cross-date it with a specimen collected from a living hemlock in the Oak Island area - an early proposal for dendrochronological analysis on the island.

This sample is separate from the charcoal layer reported in the Money Pit during the Onslow Company's excavation of 1804, which has its own entry. None of the 1804 charcoal is known to survive, and nothing in Blankenship's letter or Terasmae's reports ties the 1970 sample to the Money Pit.