Ordelle Coins are a key resource in Final Fantasy XIV, which you will need to augment gear that you have obtained with Tomestones of Heliometry. The coins will help you bring your item level to 730, so it’s something that you will need to spend time acquiring once you reach the previous level cap in the MMO.
The resource is obtained by completing a particular Alliance Raid from the Echoes of Vana’diel series and will not be easy to get a hold of.
Here is a guide that goes over everything you need to know about acquiring and using Ordelle Coins in Final Fantasy XIV.
How to farm Ordelle Coins in Final Fantasy XIV

To get your hands on Ordelle Coins you will need to complete the Alliance Raid, Jeuno: The First Walk. The raid is a part of the Echoes of Vana’diel series, which was introduced to Final Fantasy XIV with the 7.1 patch update.
You will be able to unlock the raid by taking on the “An Otherworldly Encounter in Tulliyollal” quest. The mission will be available on the patch, only after you have completed the main story missions in Dawntrail.
Once you have accepted the quest, just head to the objective markers and you will eventually gain access to the raid. Do keep in mind that you will need an item level requirement of 695 for it.
Note: You will only be able to get one Ordelle Coin per week. So make sure you are clearing the raid at least once every week to get your gear augmentations going.
How to use Ordelle Coins in Final Fantasy XIV

Once you have obtained an Ordelle Coin in Final Fantasy XIV, you will need to speak to Uah’shepya. The NPC can be located in Nexus Arcade, Solution Nine.
You will be able to interact with the NPC to exchange the Ordelle coins for “Surgelight Twine” and “Surgelight Glaze”.
Both of these will help in augmenting your Quetzalli gear. The enhancement items will allow you to get your gear level to 730. Hence, making it a much easier way of gearing up for the next batch of content if you are having trouble completing Savage Arcadion Raids.