No white sugar for jam - could I use icing sugar??

[jamandjerusalem]

Or is that crazy? I know Icing sugar has an anti-caking agent - would that mess up my jam??

Don't do it, for some reason I think it won't give very good results. Could you not get out to a shop?

No it won't set properly

DS is napping, wanted to do it while he sleeps.

Ok, I will make less with what sugar I do have.

Oh, I also have a bag of light muscovado sugar, or a bag of rapadura cane sugar. Either of those any good?