Bitburg was one of those strange, sad stories you read about in meteorite books. A 1.5 ton iron was found in the late 1700s or early 1800s and smelted before it was recognized as a meteorite. All that remains is a melted, vesicular mess.
I don’t recall seeing any other pieces of this meteorite for sale, but I’m not sure how much Bitburg is preserved in institutions or elsewhere, smelted or not. I was pretty excited when this little slice turned up in an old mineral collection from Vienna.