Hi Tim!
Very interesting,I whould have never thought of it being zinc I whould have suspected tin or like you said pewter.The brass fittings on my dagger were so tarnished when I got it I at first did not think it was brass!Good luck in finding one of these!

(no sarcasem intended)I have been looking quite some time for a good low priced choora,I have gone to the next step in the search,a freind deployed over in Afghanistan itself.But lets not let this get off the topic of Somali weapons.