Create a luxurious 3D product-style logo render of a large standalone {argument name="logo symbol" default="X"} emblem centered on a dark studio background. The symbol is thick, angular, and beveled, resembling the modern social-media X mark, with a polished metallic {argument name="metal color" default="gold"} outer rim and inner raised edges. Fill the recessed face of the letter with many small faceted {argument name="gemstone color" default="black diamond"} stones arranged in a tight pavé pattern, each stone catching tiny highlights. Use dramatic low-key lighting with bright golden rim glow, sharp starburst glints at exactly 4 visible points: the upper-left tip, upper-right tip, lower-left base edge, and lower-right lower edge. Place the logo upright on a glossy black reflective surface, showing a soft mirror reflection directly beneath it. Background should be nearly black charcoal with a subtle vignette and faint overhead spotlight haze, no text, no watermark, no extra objects. Render in ultra-detailed photorealistic CGI, high contrast, premium jewelry aesthetic, crisp bevels, realistic reflections, square 1:1 composition.