Accent a sharp tuxedo ensemble with Yves Saint Laurent's darkly decadent black Strass Swarovski crystal necklace

Layer Yves Saint Laurent's crystal necklace over a simple tank to lift your look from simple to sensational. Made from black metal and Strass Swarovski crystals, this two-strand necklace has a tiered bib at front and a lobster fastening at back of neck with a small 'YSL' charm (£695 at Net-A-Porter)