I have a Ithaca NID that I received completely disassembled and had a hard time figuring out how to reassemble it. This was a field grade gun that was engraved with Snipes by Peter Schashul in the bulino method. The Snipes on the sides have some kind of black
material in the engraving which causes it to stand out from the background, but the one on the trigger plate is shiny to the bottom of the engraving. What kind of material is used to blacken engraving? India ink?