Trapped methyl radicals in chert


We have demonstrated recently that electron spin resonance (ESR) spectroscopy can detect a narrow signal from electron gain (E′) centres in flint (Upper Cretaceous lepispheric chert)1. This signal, caused by the effect of natural radiation, is lost on heating and may be useful for dating2. ESR signals from various organic radicals are now reported in a wide variety of cherts. The thermal dependence of the signals may provide valuable information about the duration and temperature of ancient chert heatings.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    Robins, G. V., Seeley, N. J., Symons, M. C. R. & McNeil, D. A. C. Nature 276, 103 (1978).

  2. 2

    Robins, G. V., Seeley, N. J., Symons, M. C. R. & Bowman, S. G. E. Proc. 1980 Specialist Seminar on Thermoluminescence Dating, Oxford (in the press).

  3. 3

    Symons, M. C. R. Chemical and Biochemical Aspects of Electron Spin Resonance Spectroscopy (Van Nostrand Reinhold, London, 1978).

  4. 4

    Turkevich, J. & Fujita, Y. Science 152, 1619–1621 (1966).

  5. 5

    Jen, C. K., Foner, S. N., Cochran, E. L. & Bowers, V. A. Phys. Rev. 112, 1169–1182, (1958).

  6. 6

    Melamud, E., Reisner, M. G. & Garbatski, U. J. phys. Chem. 77, 1023–1027 (1923).

Download references

Author information



Rights and permissions

Reprints and Permissions

About this article

Cite this article

Griffiths, D., Robins, G., Seeley, N. et al. Trapped methyl radicals in chert. Nature 300, 435–436 (1982).

Download citation

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.