When a familiar locality yields something new that isn't easily recognized, chemistry or x-rays are often needed to resolve doubts about identification. Although there are some chemical tests easily done at home in the kitchen, one must often resort to more high-tech analytical services, which sometimes yields quite unexpected results. Like gambling, this gets addictive. Here are a few examples of recent finds that would have remained forever in I imbo i f identification had been limited to visual observation and guessing: Anglesite, Argentina Readers are undoubtedly familiar with the prolific large crystals of hematite and magnetite that have been coming from extinct fumaroles in the Payun volcanic field in Argentina. Rare crystals of fumarolic wulfenite were also reported from here (Mineral News, January 2011). Argentine dealers were frustrated when one big pocket of hematite/magnetite crystals were found coated with an ugly whitish crust of unknown composition. First they assumed it was calcite and attempted to remove it with dilute acid. No reaction.
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