Kate’s first public appearance wearing this necklace was at the National Portrait Gallery in London in 2012. At the time, she was an ambassador for the 2012 London Games. Many people viewed her choice in jewelry to be appropriate and fitting for the occasion.
The necklace features a few fine chains made of 18k gold with 4 small rose gold, yellow gold and white gold rings fitted together in an overlapping fashion. These 4 rings are positioned on the upper and middle sections of the necklace. At the very bottom is a larger ring made of the same metals. It looks like Kate’s necklace contains tiny diamonds on the rings.
I don’t think this exact necklace is available for sale from Cartier any longer. There are other versions of the Trinity necklace on their website.
The reported price of this piece is £49,000.
Kate wore it when she made a trip to NYC in 2014.