Its a blemish on the cowhide itself like a mole, or a birthmark. Sometimes we forget this is a natural product, full of imperfections, and not unlike our own skin. The cutter makes a decision when marking a hide for pattern cutting what to leave in and what is unacceptable. They often tend to leave in natural markings like that rather that ruin that whole section of leather by marking it out.
If its terribly bothersome you can ask your dealer to swap it out for you (Town and Country piece, yes?) and most likely they can exchange the casing for another.
Duane Collie
Straight answers from thirty-six years in the business.
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