Hi Brenda welcome to the show.
Black stemware gained popularity a couple of years ago, even if it defies all purpose and properties of glass. Maker is Arques, France, the world's largest automated glassmaker. These glasses are in current production. Check underneath where the stem meets the foot - with a bit of luck you'll find a mould number there, and/or a tiny raised circle that says "france". And as for folklore, nah, don't even begin to believe it.
Meanwhile, for the benefit of us all, can you post a picture so we all know what we're talking about? I might be off, you see....