Need help with Queen tang stamp

[bdev]

I need help dating this Queen tang stamp. Crowned "Q" followed by "ueen" with a circle below. The attached pic is bad but I don't have the knife in hand so it's the best I can do for now. It's listed on the attached JPEG below but is not dated.
Thanks.....Bruno

Hover over pic to enlarge.
View attachment 445926

 

[black mamba]

From your second photo it looks like '61-'71, but it is a little confusing. It says etch only, but that is clearly a stamp. What are the covers?

 

[bdev]

From your second photo it looks like '61-'71, but it is a little confusing. It says etch only, but that is clearly a stamp. What are the covers?

Winterbottom Bone. I should have mentioned that the blade is etched with Queen Steel #32 Made In USA. It's a 4 blade congress.