Best steel for letter openers?

[Eriksen]

I need a kind of soft steel which are easy to mill and engrave and can be hardened and polished to high finish.
Also a steel which can be soldered with metal decoration inlay like brass, silver or gold and made black with chemicals.

Do you know about something?

 

[Reg ELLERY]

I am going to stick my neck out and say wrought iron.
It will not harden. It can be polished to a high shine which will last if kept dry.
It can have an edge put on it but being soft will not hold.
I always say that a letter opener does not need to be razor sharp for ever just a lot sharper than my finger.
Wrought can be etched to reveal a patern depending on the manufacture it normally is full of impurities and has almost a wood grain.
If left untreated it will turn black if not polished.

It depends on the customer you are looking at. I use 100 year old wrought and that appeals to the customers I am tageting.

Just an idea may be not what your targeting.

 

[Bufford]

I have made a few letter openers over the years, but I don't make them any different than a regular knife. They are fully heat treated, and in a pinch could be sharpened and used like any regular knife.

A hardened letter opener is likely to withstand prying and other day to day wear and stress better than mild steels.