Wedgwood Ashtray

A Jasper Blue Wedgwood Ashtray, found among my mother's things when she was moving recently.  Mom believes that it was purchased by my grandmother during the late 1960's or early 1970's, but she's unsure whether grandma purchased it in Europe or America.  Because Grandma is from Norway, it could have been easily purchased there.

The ashtray features a white bas relief design in the middle of three Grecian women and a pegasus, the rest of the ashtray is unadorned. 

I've searched the web for other ashtrays that look the same, but I haven't found any that were identical.  I found several similar with the three dancing muses design and one with the pegasus design that was much larger and had white adornment around the edge.

I'm not sure if this means that the ashtray is so common that no one bothers to post pictures of it, or if it's something unusual.

I apologize for the poor quality of the photos, I'm not much of a photographer. :)