Jewel of Bless
The Jewel of Bless, along side the jewel of soul is one of the major jewels in game. It serves various purposes such as being used to upgrade item levels. The Jewel of bless can be used to upgrade an item to +6. Any further upgrade would require the use of The Jewel of Soul. Blesses can be also used to upgrade items past +9 which we'll refer to as chaos goblin upgrades.
How to Find the Jewel of Bless
This item can be found by hunting monsters. In InfinityMU the administration has put this item in many NPC's so you can buy it with zen. It isn't required to hunt it.
Places to buy the Jewel of Bless
Lorencia bar maid Lost tower NPC Noria NPC
The list goes on as there are many NPC's who offer this jewel.