Luxury Diamond Jewelry Mockup

Generate a hyper-realistic image of a luxurious round brilliant cut diamond resting on a black velvet fabric, with a spotlight shining down from above, creating a dramatic contrast between light and shadow. The diamond should be positioned centrally, with its facets reflecting the light and creating a sense of depth and brilliance. The black velvet fabric should be softly folded around the diamond, with a subtle sheen that catches the light. The background should be a dark gray gradient, with a subtle texture that adds depth to the image. The overall mood should be one of luxury and sophistication, with the diamond being the focal point of the image. The lighting should be soft and nuanced, with a subtle glow around the diamond that enhances its brilliance. The image should be highly detailed, with a focus on capturing the intricate facets of the diamond and the soft folds of the velvet fabric. The color palette should be predominantly black and white, with the diamond providing a touch of brightness and sparkle. The image should be rendered in a realistic style, with a focus on capturing the textures and reflections of the diamond and the fabric. The overall effect should be one of understated elegance and sophistication, with the diamond being the star of the show.