Tiffany & Co. T Wide Diamond Ring in 18k Yellow GoldSave over 30% on new RRP 4,050. 00. A wonderful Tiffany T Wide Diamond Ring. This is the 5. 5mm version, a current collection piece. This ring features exquisitely set white natural diamonds which form a T shape around the band. The total carat weight is 0. 13ct. The Tiffany T collection was launched in 2014, created by designer Francesca Amfitheatrof. Here's what she said about Tiffany T at the time: "It is very clean and bold. I designed the