Sorry for the long post, but this is pretty interesting.    I bought this piece in the U.S last year.  It is very thin glass and has a few chips around the rim.  I normally wouldn’t buy anything with chips but I have long wanted to buy a piece of “Mary Gregory” and they can be pricey.  I gather there are lots of knockoffs.  I do not know the provenance of my glass, but I do like it.  This is all from Wikipedia  –

Mary Gregory (1856–1908) was an American glass painter at the Boston and Sandwich Glass Company, Massachusetts  (I’ve been there – Wikipedia doesn’t know that) who helped popularize glass-painting.  She was known for her paintings of Victorian era children, and such

artwork has been referred to as Mary Gregory since the 1920s. However,  the artworks were likely from an earlier era, and the term was probably the result of marketing by the Westmoreland Glass Company. The glass most likely came from Europe. Despite this, many glass art enthusiasts continue to refer to such pieces as Mary Gregory.

The Westmoreland Glass Company of  Pennsylvania began marketing their glasswork as Mary Gregory in the 1920s. They would create glass paintings of Victorian era children in profile, and say it was done in the “style” of Mary Gregory. Westmoreland artists painted the white silhouettes on black milk glass plates, vases, glass boxes, etc. In the 1970s they also painted these scenes on blanks that they called Blue Mist – a semi-opaque glass with a baby blue tint to it. Many pieces of Mary Gregory also show up as Cranberry plates, tumbler sets, goblets, glasses and so on.