In reply to crayefish:
Yip. In the skinny single stakes chances are you'll be looking at one of these:
Sterling nano - 9.2mm 53g/m (single/half)
Mammut serenity - 8.9mm 52g/m (single, not sure about half/twin status)
Mammut serenity - 8.7mm 51g/m (single/half/twin)
Beal joker - 9.1mm 52g/m (single/half/twin)
For comparison:
Mammut 8.3mm meteor half rope is 46g/m
Mammut 10mm galaxy single rope is 67g/m
Lightest half rope that I know of being the Beal 7.3mm Gully, 36g/m!
Post edited at 10:55