OK, I took a look at my reference books and found some (not much) info....
According to Levine's Guide to Knives And Their Values (4th Edition):
Referring to L. F. & C. (Landers Frary & Clark), "used BLUE in a diamond on the handles of professional knives in the 1930's and later"
I feel, based on the size of the blade and the full bolster construction, that this knife had to be from their professional line. I would guess 1930s-1940's production. The value isn't much though, like gic mentioned above, maybe $30(ish)?...maybe more to the right person.
Thanks for sharing it with us.
*Note - I also found a reference (in Goins' Encyclopedia of Cutlery Markings) for "Blue Diamond" brand knives c. 1901-1908 trademarked used by Norvell-Shapleigh. Are these related? Who knows.
Thank you for the information Dave!! If I ever decide to restore it...I'll give you a call.
I'm glad I could help.
Hello Eric, I happen to stumble onto your post while searching for answers of my own knife. Long time ago in 2014 I rescued a knife from our recycle Centre. It told a story of neglect and age. I posted some photos on this forum but could not get factual answers of where it was made. I posted in 2014 some photos, here is the link, hope one can still see it. [img=http://s25.postimage.org/uhry1wgez/DSCF0179.jpg] I cannot recall how I managed to place the photos on one drive.
The amazing thing about your and my knife is that other than the handle, they could just about been the same knife!
Very nice vintage, and in relatively good condition. With a bit of work you may get a great performer out of it.