It has come around to that time again, when old Allagan Tomestones must be put to pasture. This time with Patch 6.4, players are getting rid of the helpful Allagan Tomestones of Astronomy. It’s time to move beyond their use.
The new high-end tomestones are Allagan Tomestones of Comedy. As always, these new tomestones have a total cap of 2,000 and a weekly cap of 450. That’s as many as you can earn from one Tuesday reset to the next. The old upper-tier, Allagan Tomestones of Causality, are now uncapped. This means you can farm an unlimited amount per week, up to the total inventory cap of 2,000.
The previous lower-tier tomestones, Allagan Tomestones of Aphorism, are no longer obtainable in the game. Any Duty Finder content that used to award these will now offer Causality Tomestones instead.

How to Exchange Tomestones of Astronomy
So, what do you do with these discontinued tomestones? Well, you can spend them prior to the patch if you really have a larger number lying around. With Patch 6.4 live, you can go talk to Auriana in Mor Dhona (X: 22.7, Y: 6.7). The last option in her menu will be “Allagan Tomestone Exchange.” Select this to exchange your remaining Astronomy Tomestones for Causality Tomestones.
This will not be a straight 1:1 conversion, which is why we stress that you should probably spend the Tomestones now unless you’re already at cap. The conversion rate these days is typically 4:1. Meaning if you have a full 2,000 Tomestones of Astronomy, for example, that number will convert to 500 Tomestones of Causality. The four-to-one conversation rate remains the same in Patch 6.4.