A Jewel of Harmony can add different Additional Options based on the type of item it is used on.
List of Jewel of Harmony Options:
Weapons:
Strength Stat Increase
Agility Stat Increase
Energy Stat Increase
Attack Success Rate Increase
Attack Power Increase
Critical Damage Increase
Excellent Damage Increase
Skill Attack Power Increase
SD Reduction Rate Increase
5% of Mana Converted to Attack
Sets, shields:
Vitality Stat Increase
Defense Increase
Maximum AG Increase
Maximum HP Increase
Maximum MP Increase
Damage Reduction Increase
SD Ratio Increase
Convert 10% of Mana to Life