A surgical instrument comprising a symbol formed in or on a smooth surface surrounding the symbol, wherein the symbol comprises a plurality of angled surfaces over at least part of the area of the symbol, wherein the angled surfaces define a plurality of parallel ridges and grooves in the symbol. These ridges and grooves create an improved contrast for the symbol relative to the surrounding surface by a combination of different specular reflection of incident light compared to the surrounding surface and shadows formed by the ridges and grooves. A method of marking a surgical instrument with a symbol formed in or on a smooth surface is also described. The method comprises forming a symbol in or on a smooth surface of the surgical instrument and forming a plurality of angled surfaces over at least part of the area of the symbol, wherein the angled surfaces define a plurality of parallel ridges and grooves in the symbol.