This patch will remove all acquisition methods for tomestones of esoterics, with all esoterics items becoming purchaseable through other means and the usual exchange options available. The patch will also remove tomestones of law altogether, meaning that if you’re still sitting on a pile of law tomestones that you’ve never exchanged, you’ll need to take care of that before the patch goes live or lose them forever. Poetics tomestones, meanwhile, remain more or less unchanged.
Final Fantasy XIV, and if you’ve been around for previous patches you know that means you’re going to need to fuss around with your Allagan tomestones. The newest addition to the tomestone family are the tomestones of scripture, taking the spot of the new limited-per-week currency that you get for doing the highest content. But players holding on to older tomestones will need to take action before then to make sure nothing is lost on September 27th.
Source: Official Site