Rio Tinto radioactive capsule lost in Australia: what it is and why it is extremely dangerous

The radioactive capsule (6 by 8 millimeters) that allegedly fell from a truck in Western Australia, between Perth and Newman, is extremely dangerous. The company in the crosshairs, already criticized for having excavated a sacred site, said it was “sorry and very worried”. But what is this capsule? The device, made of silver, was used at its Gudai-Darri mine site in Western Australia to measure the density of the iron ore that the mine extracts.
It measures just 6 by 8 millimeters, yet it is “capable of causing serious damage to health” (the Associated Press even defined it as “potentially lethal”) because it contains radioactive cesium-137: a spokesman for the Anglo-British mining giant admitted it. Australian Rio Tinto about a small capsule that the company simply «lost» between Perth and Newman in Western Australia.
It is a “density gauge”, commonly used in the mining industry to stay away from, which could cause serious illness if touched. The alarm was shared by numerous newspapers. “The fate is clearly very worrying and we are sorry for the alarm it has caused,” a company spokesman told the BBC.
“Exposure to the capsule is equivalent to receiving in a few moments the amount of natural radiation that we receive in a year,” explained the regional health director, Andrew Robertson.
The reasons and the dynamics for which it would have been lost remain to be understood. The last recording we have is that it left the Gudai Darri mine on January 12 aboard a specialized vehicle equipped with a Geiger counter, which never emitted any alarms. The alarm on her disappearance was given only on January 25th.