I have recently noticed that when my car is idling there are some small sort of black puffs of carbon dust coming out of the exhaust. Its not really a lot but i would like to know if its fixable.

Sounds like it's running a bit rich or perhaps the cat is breaking down, hopefully there'll be some mechanics coming along soon.

Is it the diesel, or 1.3 or 1.6 petrol?

Its a 1.3 pertrol 8 valve

Only thing that I can think that would send visible particulates out is if something inside the exhaust was breaking up.

Does it use any oil at all?, if it does this could be the cause . if not try putting a dose if redex in the tank, and give it a good run, then try it

There's a number of thing it could be.

Has the oil or water consumption increased recently? If so, suspect the head gasket.

Has the fuel cons...recently? If so, suspect it's running very rich intermittently; probably injector(s) or llambda sensor.

Are there any tinny rattles from underneath on bumps? If so, suspect cat or silencer breaking up internally.