A larger, statement-making version of the best-selling Signature Midi Knockout Studs , the Signature Large Knockout Studs feature multi-faceted, brilliant-cut gemstones that make an impact for both day and night. Gemstone: Midnight Blue (Man-Made). With a lower environmental impact than naturally mined gemstones, our Man-Made stones are a highly durable alternative offering impeccable colour consistency and a wider variety of hues. Gemstone Diameter: 10mm