Carbon Layer Streel Bangles3 Separate layers. Cornstarch based Biopolymer reinforced with Steel Powder Carban Layer Collection Carban layer collection, 3rd collection of the brand is the extension of the first collection named Carban inspired by the geometric forms of Shah Abbasi Caravanserais dome in Meybod, a city in Yazd province in Iran. This collection includes a three dimensional earrings, a set of bangle and ring, each containing three pieces (layers) different in shape