[QUOTE=ALEX]
Hello Alex,
The Qama is NOT single edged. The Qama is double edged... and identical to the Kindjal (one example is in the photo provided by Ibrahiim). If it is single edge, it is most likely a Qaddara wrongly named.
Qaddara is single edged, with slightly curved blade towards the tip (like the one in the original photos posted by Ariel).
Best regards,
Marius
PS: I assume that for every type of sword, you may find some exceptions that cannot be precisely classified as they display hybrid characteristics. But exceptions only confirm the rule.

PPS: You may find it useful to have a look at the thread posted by Miguel related to Quamas, Qaddaras and Kindjals.
And you may want to get the book "Arms and Armor of the Caucasus" by Kiril Rivkin, which I believe is the best reference book on this subject.