This Goblet is Unmarked; Chalaine? McKee?

It's 6½" high, ~3⅜" rim diameter, 3" foot diameter.
The bowl is blown; the rim, ~.060" thin, is cut (pic 2)
The rim OD varies no more than .010".
The stem & foot are one piece, and attached to the bowl (pic 4).
The foot center 2" is recessed (pic 3)
When plucked at the rim, it rings like good crystal.
The color is absolutely uniform throughout.
When exposed to blacklight, it becomes completely white.

It is without any mark. I learned only today of McKee, and Chalaine.

Acquired in mid-1990's from a known, loved & trusted dealer, as a gift, after I admired it in her shop. She taught me a lot.

The pattern of the stem & foot look classical...beyond that I have no idea how to further ID this piece. Your help is solicited...and Thank you!

 

possibly Imperial Glass 'Provincial'; also made by Portieux-Vallerythal

Imperial Glass-Ohio, Provincial Blown (Turquoise) | Replacements, Ltd.

Portieux Vallerysthal, P1V4 (Turquoise) | Replacements, Ltd.

 

Looks more like the Imperial Glass Provincial, tho' the difference is subtle. Excellent Work, TallCakes...Thanks!