It was a hard black curled piece, about 3/8" long, and skinny. It was imbedded into the thigh, and when I pulled on it, it resisted coming out. Looked like the shape of very tiny slug, but could it have poossibly been a piece of the liver or heart, or a blood vessel? I googled and couldn't find anything similar. It was at Lidl, which we don't normally go to. Aldi is our new go-to place! We love it, and will continue to buy meat there, especially since everyone is giving such good reviews!