Mystery crystal from Atlas Mountains

What is this mystery crystal?

Fascinated by its colour, reminiscent of amethyst but it couldn't possibly be, I was seduced into buying it for an astronomical sum from a Berber high in the Atlas Mountains.

Surely it was genuine, though what it is was genuine of I did not know.

Having purchased it after some hard bargaining, Berbers are notorious tough negotiators and language is no barrier I later consulted my Rough Guide to Morocco.

Do not they said under any circumstances by crystal from the Berbers. It is dyed.
OMG! I linked my finger and smudged it on the outer casing?sure enough a fine black dust came off.

Oh well, it looks pretty.