This appears to be a 
vintage clear pressed glass trinket dish or ashtray. The piece often features an embossed or etched design of birds, such as swallows or doves, in the base, consistent with a vintage Art Deco style. 
Key Details
  • Material: It is made of clear, pressed or crystal glass.
  • Design: The rectangular shape and the detailed relief design of what appears to be a bird and possibly foliage suggests a specific pattern.
  • Purpose: While it can serve as a small trinket or jewelry dish, it is often marketed as a vintage individual ashtray or a cigarette box cover (if paired with a lid).
  • Potential Manufacturer/Style: Similar items are associated with manufacturers like Duncan Miller (often the "Mallard Duck" pattern) or Verlys (often "Swallows" or "Doves" pattern). These pieces were popular during the Art Deco era of the 1930s to 1940s. 
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