Vintage 6.5" Ruby Red Glass Decanter with Flat Stopper Rainbow? Blenko? Whiskey

Description

What a stunner!  This vintage Ruby Red Decanter with flat stopper measures approximately 6.5" tall (including the stopper)  The stopper itself is hollow with an open end and measures approximately 3.5" long. There is a small amount of scratching on the bottom underside, there is also a small air bubble in the stopper and some roughness on the inside of the rim.  There is also a glass "blob" around the rim of the decanter (which you can clearly see in photo 4) but the rest of the piece is in good condition. It is an eye catching piece, that would make a wonderful addition to any collection.  Based on my research, I believe to to be made by Blenko, however an Ebayer has told me that they believe it is Rainbow Glass. There are no stickers or makers marks of any kind so I cannot guarantee either, please do your research BEFORE purchasing.
I am not a professional but do my best to describe what I see.  This is NOT a new item, therefore it is not perfect. If you are looking for perfect, this may not be the item for you.  Please view all photos and ask all questions before purchase and thank you for looking!