I was sent the images to my "Scotlands Glass service address", asking for help with the signature and maker. The item measures 3.5"H x 3"W and weighs 1 lb 4 oz.
The owner lives in the United States (where he found it), but believes it to be of European origin. He also assumes it to be a small vase or penholder. Considering the size and the shape of the cavity I wouldn't exclude a perfume bottle, however, with the stopper missing. Signing the item on the side, close to the base, would be more likely American, I guess.
Any comments are welcome - Thanks and best regards - Wolf