How is this engraving done?

[webradbury]

I want to start adding a little embellishment to my knife bolsters but I can’t figure out how this type of border is done. I’ve tried and tried with different shapes of gravers and chisels but I cannot duplicate these cuts. Anyone know what tool/technique is required?

[Nordnecker]

It is done with a square graver. You roll it to the side while tapping in. Then roll it back out. The little facets you see are the taps from the hammer.

[LRB]

You really don't want to duplicate those cuts shown. They are way too ragged. You can also do it with a square push graver. Push in with a lean , then flick it out. With just a little practice you will get it. Or, you can also come in with a lean from both sides.

[Lzymtlsmth]

You can see the tool progression makes, I would say it was cut hammer & chisel.
For this type border I use a flat cut from an 1/8” tool bit. Start with the tip of the tool on its side tap in several taps then start lowering the handle & lift out.
Bracelet shown is cut that way.
https://ibb.co/y6bF5FL