AI Appraisal Estimate

This item is a vintage costume jewelry brooch featuring a distinctive Mid-Century Modern geometric aesthetic. The piece is constructed from two triangular segments of marbled green plastic, likely Lucite or Celluloid, set within a gold-toned metal frame. The green material exhibits a pearlescent, 'end-of-day' swirled pattern with varying shades of lime and seafoam green, imitating the look of natural jade or malachite. The metal framework appears to be gold-plated brass or a similar alloy, showing a thin, elegant bezel that emphasizes the sharp angularity of the design. The item is medium-sized, approximately 1.5 to 2 inches in length. In terms of condition, there is visible surface wear including fine scratches on the plastic inserts and noticeable tarnishing or loss of plating on the metallic edges. The pin stem is visible at the back, appearing straight though it shows signs of age-related patina. No maker's marks are visible in the provided view, but the style is consistent with 1940s-1960s costume jewelry manufacturing. The craftsmanship reflects mass-produced quality typical of mid-20th-century fashion accessories, valued for its bold color and architectural silhouette.

I have conducted a visual examination of this Mid-Century Modern geometric brooch. Based on the marbling density and the style of the bezel setting, I suspect the inserts are thermoset Lucite, a common high-quality plastic favored in the 1950s for its depth of color. The 'end-of-day' swirled effect is well-executed, successfully mimicking semi-precious stones. However, the condition is fair to good; visible surface abrasions on the plastic and significant plating loss on the gold-toned frame—likely a base metal alloy—negatively impact the valuation. The market for unsigned Mid-Century costume jewelry remains steady, driven by the 'Mod' aesthetic. This piece is a typical example of mass-market fashion accessories from the 1950s or 60s. Comparables for unsigned geometric plastic brooches of this era generally sell within the $40 to $75 range depending on the vibrancy of the color. The lack of a maker's mark (such as Trifari or Coro) limits its ceiling in the collector market. Critically, a visual inspection via imagery cannot definitively distinguish between Celluloid and Lucite, which could affect long-term preservation needs. A definitive appraisal would require in-person testing, such as a 'Simichrome' test for Bakelite/Celluloid or a hot water scent test to identify the specific polymer. I would also need to examine the pin mechanism for structural integrity and hallmark stamps under 10x magnification. Without physical access, I cannot verify the stability of the adhesive used to secure the triangular segments.