Blenko (?) brown glass ashtray

This ashtray is about 4.75" on each side and is 2.25" high. It weighs 3 lbs 9 ounces. The bottom is scored, similar to the orange and red turtle I recently posted. This pushed the bottom out a bit and there is spot where the glass is rubbed as a result. A thrift shop find today and I paid big money for it ($6). I immediately thought "Blenko" when I saw it and it may be by them. There are similar ashtrays in the 1990 catalog, though slightly smaller and much larger. Still looking at catalogs! A nice chunk of glass. Calling it "Blenko" but leaving it a mystery until I finish my research. Thoughts welcome.