In 2009 M. Fricker (ETH Zurich) was able to test a Scurion P4 under the extreme conditons of Naica Cristal cave:
Largest natural selenite (some 11 m long and 1 m thick), 290 m below mine entrance, was discovered in Naica mine, Chihuahua, Mexico. The Ag, Pb and Zn mine is owned by Industrias Peñoles. During regular mining activity, the geode was discovered in 2002, soon after which exploration and documentation began by 'La Venta - geographical exploration' for speleoresearch & films and C/Producciones. Access to the cave was possible through the mining galleries and only due to excessive pumping of ground water to lower the natural aquifer.
In the Cristales cave the temperatures range from 45 to 50 °C with relative humidity approaching 100%. Such harsh environment is lethal within a few five minutes and requires protective gear to prolong working time.
The scurion worked just fine, although after equilibration to the high temperature, it was no longer possible to switch to different light modes anymore. This was due to the interal sensor of the Scurion® lamp that prevents it from overheating. After going back to the galleries (significantly cooler temperature) and a few minutes of cooling, it was again possible to switch to all modes.
M. Fricker, 2009
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