Mystery Vase, late 1800"s

This was my great grandmother' s, and may have been handed down to her by her mother. My grandmother, one of eight, grew up in Montclair, NJ, and raised her family in Summit, NJ. This vase was always on display in my grandmother's dining room. I also inherited my great grandmother's lovely old Royal Worcester pitcher, but that one is easy to identify. This is a total mystery! Other than the little hand painted numbers "0512" on the bottom, it has no signature or identifying marks. It has a Deco feel but I'm really not sure if it's that new. The thistle on it is almost magically part of the glass. It doesn't look painted, except in a few spots. It almost looks as if the design was blown into it. Does anyone recognize this type of vase? Thanks!