My paper in Health Physics in 2001 relates to the topic of "natural" radioactive mineral specimens of the sort displayed at the British Museum. Of course, it was written in a pre-9/11 world. See: R.J. Barish. Radiation Protection Analysis for a Rare Mineral Specimen. Health Phys. 81 (Supplement 2):S67-S69 (2001) Robert Barish, Ph.D., CHP