These are interesting, I have come across several over the years. Can you show a photo of the top of the item, please? When I first saw one of these, I suspected it was not headwear at all. It looked sort of Bedouin or some Northern African/Arabian country thing to me. Then I thought it might be an antique purse, mistakenly thought to be a hat of some kind. On Ebay I have seen some antique beaded bags with no drawstring or handle, put on a mannequin head and called "antique beaded skullcaps". Then a few years later I found another like yours, and that made me wonder what exactly this was, and if it was indeed for the head. A good reason for my thinking this is the size of the circumference was always much too small for it to fit an adult head, or even fit a small child. Yours is larger, as you say it fits you, but I am curious what the measurement is? Is it damaged at all on the part we cannot see, which would in effect increase the size? I do see some damage in front as it it was stressed and broke.
The seller on Etsy claims their item is sterling, but not marked. If it is sterling, that leads me to suspect it is a purse (or a cover for something or?) and not a hat. While metals were used for headwear, especially in the art Nouveau era and early 20th century, I have not come across one that was sterling. I am curious to find out. Also, that seller says the circumference is only 20 inches, which again is much much too small to fit any adult head.
Is it a good weight? That is, does it feel a bit hefty in the palm of the hand?