The 18kt Yellow Gold Vermeil Urban Bar Necklace With Black Onyx by Jewel Tree London. The Urban Bar Necklace is a clean geometric jewellery design that is edgy-elegant with a strong individual style statement. This contemporary necklace design features an elegant Black Onyx baguette that has been hand-cut to our design specifications and set in 18kt Yellow Gold plated Sterling Silver. Please note that there may be a slight colour variation in the stones from piece to piece due to its natural origin. About The Designer: Jewel Tree Londons designer and creative director Deborah Zama creates timeless and elegant jewellery inspired by architectural designs, materials, and forms, featuring a range of semi-precious stones and refined metals. Deborah has innovated the design process by combining traditional practices with modern technology each of her pieces is individually crafted by hand. To view more of this designer\'s collection please visit Jewel Tree London.