John, this info comes out of the revised Smithers, basically the "Bible" on Southern African mammals:

a) Matetsi Zimbabwe
Males 51.8 -71.3 kg (n=13), average 59.7kg
Females 28.2-34.9 (n=7), average 31.5kg

b) Waterberg, Limpopo province, RSA
Males average 58.8kg (n=6)
Females average 34.9kg (n=6)

c)Northern- Eastern adn Western Cape, RSA
Males average 30.9kg (n=27)
Females average 21.2kg (n=9)

d) Kruger Park, RSA
Diffrenciate between old-, Prime-, and sub adults and large cubs:
Old adults
Males average 63.1kg (n=5)
Females average 37.2kg (n=6)

Prime adults
Males average 58.2kg (n=3)
Females average 37.5kg (n=6)

Sub adults
Males average 50.9kg (n=6)
Females average 30.1kg (n=3)

Then in a seperate study, for Northern Namibia they found:
mean weight between 18 leopards:
males 44.6kg and females 25kg.

In other words, a leopard female can weigh from 25 kg to 55kg (the heaviest I have personally hunted with a client), and a adult male from about 45kg to 83 (once again the heaviest I have personally hunted.)

Now of course, a lot of the weight depends on when they have last eaten, as they can eat up to 20% of their body mass in one sitting, and as shakari has pointed out, other factors.
More important, NQC minimum measurement is 32cm at the moment, this cat measured 35.3cm (same measurement as SCI, just in cm)