Actually I use, fine silver, cupper, and gold. Since I use fine silver (99.999%) it will not oxidize much during bluing, the cupper will become a little darker, and the gold will not change since it is 24 carats. As for the black, it is just shading. There is almost always a space between the edges of the pattern and the beginning of the shading, so the ornaments always appear clearly on a darker background (after bluing), as will the shading. The shading give an additional “color” it is also use to give volume and movement to the ornament.
