Matthew Hengge 12 September 2016 Engagement Rings, Coloured Gemstones Kate and John's engagement ring: A little bit of blue Matthew Hengge 12 September 2016 Engagement Rings, Coloured Gemstones There's nothing quite like a custom designed piece created for your special someone. Wanting a unique engagement ring, John came to us with a few requests in mind. Here's the story behind their beautiful piece.