New Delhi, Aug. 27 -- Taylor Swift's 8-carat diamond ring may have made headlines, but it wasn't the only jewel worth noticing when she and NFL star Travis Kelce announced their engagement. The singer paired her dazzling ring with an equally rare Cartier timepiece-- a detail that only sharp-eyed fans spotted.

The couple shared the news on Instagram on Tuesday, posting a series of photos with a playful caption: "Your English teacher and your gym teacher are getting married." While the vintage-inspired yellow gold ring caught immediate attention, Swift also wore a Cartier Santos Demoiselle watch set with diamonds, made in the same metal.

According to Eugene Tutunikov, CEO of SwissWatchExpo, the watch once retailed at $27,300 and now resel...