This story is printed on the inside front and back covers.
The rather unmuscular figure under the tree, sketchy hands and inking makes these drawings the work of Maxon. He drew many of the "Young Hawk" stories in Lone Ranger, and some early Tarzan. Also one story in Indian Chief #6.
Pencils credits from French magazine Back-Up #14, provided to the GCD by Stephane Petit (25 April 2009).
Additional art infos come from the John Buscema checklist built by Jim Vadeboncoeur Jr and Michel Maillot.
Script credit source (Gaylord Du Bois's Account Books Sorted by Title compiled from the original account books by Randall W. Scott) states: "The Copper Knife (synopsis). 16p. For War Eagle. Sent March 5, 1950." ~Dave Porta
The artwork here is identical to Jon Small's signed stories in this series, Four Color #290, The Chief #2, and Indian Chief #3. The best clue is the heavy inking, and the close up faces, with many thin inklines along the cheekbones and upper lip. Also the scenery, and movement of the figures are similar.