Some imperfections in glass, I believe from manufacturing.

Shape: Round
Color: Blue
Item Diameter: 4.5"
Material: Glass
Suitable For: Cigarette
Brand: Unmarked
Type: Ashtray
Original/Licensed Reproduction: Original
Style: Mid-Century Modern
Theme: Floral & Garden
Production Style: Art Glass
Production Technique: pressed
Country/Region of Manufacture: Unknown
Finish: Glossy
Product Line: Bubble