An update on Irradiated Gemstones

"... Eight of the nine batches of gems, which averaged around 500 carats each, showed only background levels of radiation, while one registered at "twice background." Background levels refer to radiation that is picked up merely because a survey meter is turned on because there are already low levels of radiation present in the atmosphere. By measuring "twice background," it implies that there are low levels, but nothing that would be considered dangerous or hazardous to health."

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Courtesy - diamondvues.com