cable for long xlr microphone cables

["Jez" tempjez]

there could well have been a post on this subject before but I couldn't fin=
d one, so....

I've been making up some long cables (XLR - 50m) & using a few different ca=
bles, researching others. I have one simple question first:

Q: even at high cost some cables use braided copper shield & some use braid=
ed aluminium shield. Does anyone know what the actual difference is between=
 the two in a practical sense ? I somehow assumed copper was better but som=
e of the most expensive cable uses aluminium too.

on a wider point, perhaps some thoughts on the best cable each of us have u=
sed out in the field would be useful ?

Klotz
Mogami
Van Damme

are all makes i've used various cables from & seem to be v.reliable.