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In Dowsing the Dead, Mia makes bracelets for the others each with a gem that should support them with their powers. Most of the abilites get a certain gem, Clive also gets a bracelet although he does not have an ability. She mentiones she had already made most of the bracelets but the gems Peridot and Malachite were hard to get hold of.
Dax gets Malchite and Clive reads "Important protection stone. Has to be handled with caution-can be toxic! Heavens! You sure Mia really likes you? Um ... yep-stone of transformation-that's you, alright. Used as an access stone to other worlds ... blah blah ... amplifies energies-both positive and negative.". And Mia says "The stone of transformation. Be careful with it, Dax. It'll show you things how they really are. Things you might not want to see"
Gideon gets the stone Serpentine
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