I haven't yet seen any gold in zone 777 and you seem to get quite some amount of it, maybe type of metal is regional?
This is strange, I have scavenging 100 too and find HQ, VHQ and (some) Master items.
Okay, my perception is lower than yours (70), not sure whether perception has influence on quality of items.
Added after 7 minutes:
I'd reckon your results show that perception might be almost as important as the scavenging skill itself. MrDDT has 95 perception, Vito has 70, you have 12. That could explain why you don't see "rare" metals.
Granted, I've not found any recipe since the patch too.
Foraging in Xsyon seems to be different from scavenging (or not yet implemented correctly). I've got 100 skill in Foraging too and every single berry/plant/herb I find since I got skill 100 is of "supreme" quality.