Thanks guys,
The engraving is done with chisels called gravers that are ground specifically for cutting metal. There are no rotary tools, photo etching or lazers on my engraving bench. Its all actually cut.
Eisen Faust, there is a very good engraver in Christchurch, New Zealand named Andrew Biggs.
Here is a link to his website.
http://www.engravingarts.co.nz/
Andrew is a super nice guy and if your interested in engraving it would be worth contacting him. I don't know how close you are to Christchurch but Andrew is the only engraver I know in NZ.
Ray