game resource icon, a single iron ore chunk or one metal ingot, dark grey metallic surface with a subtle silver highlight, thick bold silhouette readable at tiny sizes, centered composition filling the frame, flat stylized 3D render, soft cool studio lighting with one specular highlight, single object only, high contrast against a muted circular background, clean simplified metallic shape, no text, no watermark, mobile strategy game UI icon, vibrant steel-blue tones, square 1:1, crisp clear at small size, icon-style not illustration