SLX 9spd triple complete is 889g claimed
XT 9spd triple complete is 853g claimed
So 36g difference (and usually around £36 sort of figure difference)
Bottom bracket is the same between them
IIRC
SLX inner chainring is steel
XT inner chainring is aluminium
SLX middle chainring is steel teeth/’composite’ ring
XT middle chainring is steel teeth/’carbon’? ring
SLX outer is aluminium (as is XT) but SLX appears much chunkier
I always suspected there would be little between the arms. 6grams seems about right
[SLX double bash is ~1000g complete, same BB, but as above steel inserts, I seem to think its steel axle? has all steel rings (incl. 104BCD 36T) and as above (104BCD 36T) bashring not light]