Preliminary identification
Photo reference
2 uploaded photos
Overview
A beautiful set of four footed tumblers in the iconic 'Block Optic' pattern, boasting a vibrant green hue. These pieces are made of uranium glass, meaning they contain trace amounts of uranium dioxide that cause them to glow a brilliant, neon green under a ultraviolet blacklight.
Story
During the dark days of the Great Depression, American glassmakers added trace amounts of uranium to their batches to create cheap, cheerful tableware. These glowing green vessels brought a much-needed splash of vibrant color to struggling households.
Maker / Origin
Founded in 1900 in Columbus, Ohio, the Federal Glass Company was a giant of the American 'Depression Glass' industry. They pioneered mass-production techniques that allowed them to produce millions of affordable, beautifully patterned glassware sets for everyday families.
Condition & Value
The tumblers appear to be in good vintage condition with no major cracks visible. There is minor surface wear consistent with age, and the rims should be closely inspected by hand for tiny flea bites or rough spots, which are common in molded glassware of this era and can reduce value by 20-30%.
Full Research
Sold comps, value drivers, and venue guidance pulled from recent auction results.
Build on this identification
Layer in sold comps, value drivers, and venue guidance.
Comparable demand stays strongest where maker, originality, and venue confidence line up. Broader examples still trade, but the range tightens quickly when provenance, condition, or selling lane fit is missing.
Best Venue
Specialty auction or a focused dealer with buyers already in this lane.
Signed example with light edge wear and original frame.
Comparable format with stronger provenance and cleaner surface.
Smaller related piece with visible craquelure and trimmed margins.
Period match with softer condition and weaker subject matter.
Close market lane comp with similar material and presentation.