A satin lapel is the modern definiton of a tuxedo. However, this one detail does not classify a suit as a tuxedo – there are other elements that make up a tuxedo.
There are many ways that you can spruce up a formal black suit with satin. You can create a wide or skinny satin border or do a solid satin lapel. The addition of black pique stitching could also create an interesting detailing on the satin. Velvet would suit a wool that lacks sheen.