Blushes Turned Dark Blemishes - Hand-colored Antique Ambrotype of Mother and Child

I've always looking for antique photos--and anything really--made better by the chance effects of time, and this is very much one of those. I believe originally the cheeks of this mother and child were given a pink hand-tinted blush, but over time that blush turned to near black, now looking like dramatic blemishes or diseases of the skin, which seem as if threatening to overtake their faces entirely. The result makes me think of Hawthorne's The Birthmark (written not very long before this ambrotype was taken) portraying scientist/philosopher Aylmer's obsession with his beautiful wife's birthmark and dream of it going all the way to her heart. 

Sixth plate ambro, in half case 3 1/4" x 3 3/4."  One side of the case  is split from the other though the latch will hold them together at one side.