Appears to be heavy brass under the blade and at bottom. Does show green color on brass parts. Blade shows RH Ruana "M" 1977.
Sheath and knife could use cleaning but appears to be a very nice knife. Blade measures approximately 6.5", total length is 12.25". I don't have a lot of knowledge about these knives but will do my best to answer any questions you may have. Thank you so much for looking and please see my other auctions for more knives and estate finds! RUANA Marked M Custom Hunting Knife & Sheath" is in sale since Friday, November 24, 2017. This item is in the category "Collectibles\Knives, Swords & Blades\Collectible Fixed Blade Knives\Vintage Fixed Blade Knives\Custom & Handmade". The seller is "suzettekoz-9956" and is located in Central Point, Oregon. This item can be shipped to United States.