While eternity rings had already been in use for over a century by the early 1900s, the Art Deco era's focus on precision and innovation saw the development of the now-classic channel setting and used it at length for diamond and gem-set eternity bands. 

Very good vintage condition with wear in line with age and use. c1930s. Originally manufactured in US. 

Details:
• Platinum, unstamped but tested
• Size 4.5 and do not recommend resizing 
• 31 mixed cut diamonds (old European cut, transitional, and brilliant) approximately 0.45 carat total weight
• Ring measures 2.2mm wide and 1.7mm thick
• 1.8g