Black carrying lilac?

[Paige McDonald]

I'm getting a lilac/black pair from someone and she said the
parents were both black but carried the lilac recessive. Here's
her message:

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They are brother and sister. The parents are both black but carry
the
recessive for lavender.
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What would the 'recessive for lavender' be? But what I'm really
trying to figure out is what the gerbils and/or the parents
genetics are, so I can register them with the AGS. I'm pretty
sure they've only had black and lilac. Thanks,

Paige