This is the Perfect Ed / Max Magic Jewel for Level 18. Needs to be close to Perfect on a Magic Jewel to keep.
Rare Jewel it's only possible to get up to 20 Ed / 14 Max with 3 Mods so you'd need a 4th Mod like Ar or Min Dmg to keep those.
Rusty Jewel of Carnage > 20 Ed / 15 Max