DUNCAN, GEORGE & SONS No. 0090 (OMN)
• AKA: Open Cryptic; Zippered Block
• Duncan, George & Sons (Pittsburgh-PA, Company Operated: 1874-1891), Introduced: 1887 Introduced
• NOTE:
• Motifs: (Bands/Rings), (Squares/Rectangles), (Ladders/Zippers)