I don't know what stone you're referring to but just bear in mind that even if a tourmaline has copper in it and therefore may be Cuprian this DOESN'T mean it would be considered to be "Paraiba" or "Paraiba like". Colour and the right composition is the determining factor. I've seen lab reports that state something like "this stone could be considered a "Paraiba" or something like that but they've been shocking and the only thing linking them to a proper Paraiba has been the copper content as nothing else about the stone radiated Paraiba.
Are you experienced with a loupe and looking at inclusions? If so, you may be able to see copper needles and sift them out from other inclusions.