I have a real liking for Johnny Sheffield in these “Bomba meets…” movies. Besides bringing someone like "Kurt" from "The Sound of Music" (1965) to mind, he’s consistently entertaining as an example of straightforwardness and goodness within a jungle setting that's about to be threatened/taken advantage of/ruined by anyone who believes they have the right idea… In this particular story, the protagonist becomes involved with some unpleasant diamond smugglers pretending to be scientists while mistreating and holding captive local people in their search for "The Mountain of Diamonds." Naturally, it was shot in California, and the animal sequences seem like standard footage; however, the hero’s naivete and the story's appeal—along with Leonard Mudie’s portrayal of a tired Scot—brought a smile to my face. I thought the somewhat choppy ("Me Tarzan, You Jane") style of dialogue from “Bomba” was a bit much; his background is pretty obvious because he can converse with animals – and also because of his loincloth; but I still had fun watching it.

Source on TMDB