Metal Engraving

I had got an idea of engraving a polished coin….

3mm Stainless steel cut to size (£23.24)
http://www.ebay.co.uk/itm/3mm-Stainless-Steel-316-Disc-Circle-Washer-Round-Plate-Blank-Profile-ANY-SIZE/181820700004?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160727114228%26meid%3D2f0c7a7465334dac9eaf049c08dc9fe4%26pid%3D100290%26rk%3D3%26rkt%3D4%26sd%3D301401583175&_trksid=p2060778.c100290.m3507

Diamond engraving bits
http://www.ebay.co.uk/itm/30Pc-DIAMOND-BURR-ROTARY-TOOL-BIT-SET-Dremel-Engraving-Tiles-Stone-Glass-Wood-/311770868920?epid=844343710&hash=item4896fdecb8:g:PEgAAOSwZQRYY5BV