Maybe he made a mistake, maybe they looked black to him or to the person writing up the description so they were misidentified? Maybe he just doesn't know the difference? Nobody can know everything about everything, any vendor who deals with masses of material from all collecting categories is bound to make the occasional mistake. I have some great and rare items that I purchased cheaply because the dealer misidentified them or missed a detail. Collectors need to be their own experts in this case. I would suggest that a collector should know about that which he is seeking, before making a purchase.
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