Jeweling More Lunar Charm Shenanigans

Loot bonus
[Lunar Charm][Infused Gold]
[Infused Gold][Old Treasure]
[Lunar Charm][Old Treasure]
+22% to +28% loot bonus (good for necklace)
+10% to +16% xp bonus
-204 durability

That's the no downsides recipe, you can also do 1x Lunar Charm and 5x Ancient Coins for up to 40% loot bonus, if you can stomach the roughly -50% walk speed.

XP bonus
[Lunar Charm][Aged Medallion]
[Aged Medallion][Old Treasure]
[Lunar Charm][Old Treasure]
+18% to +26% XP bonus
+14% to +20% loot bonus
+8% to +10% spell damage
20 Int req.
-224 durability

As always, Ancient Coins slap can get you more at the cost of crippling walk speed.