Question about Folklore tomes

Recently got 2 of my 3 gathering jobs to 80 and I have purchased enough tokens to purchase a folklore tome, I tried looking up detailed info about the tomes but no info regarding if the knowledge of said nodes are perm or on a timer (not like collectible nodes and such). My question is a simple one:

-Is there a time limit on how much I can collect before having to buy a new tome or is the knowledge of those locations perm?
-If said nodes are on a separate timer, how much time will I have before buying a new tome.

I Thank you in advance for taking the time to answer this question...

The items are permanent once used, the timed portion refers to Eorzea time. So if a node spawns at 2pm/am Eorzea time you have a 2 hour in game window to gather from the node before it disappears before it’s next time slot.

Thank you for that info and also does that also include the older Folklord tomes as well?

Yep, once you acquire and use a book you will always be able to gather the items those books unlocked, as long as you’re within the nodes timeframe. That being said there are some nodes that are times that do not require books to unlock, just need to be within the time frame they’re available.

This is easier to understand if you look at it from an ingame/in character perspective. By reading these "folklore books" your character learns legends about hidden nodes. "If you look in the southern hills near the lone cypress tree at 5oclock, the shadow falls on the spot where a hidden vein of _____ ore" type of thing. So once your character knows that, you the player get the ability to see these new nodes during their spawn windows. If youre in the zone during the spawn window and have truth of mountains/forests/oceans active, you get a message that you sense a legendary ore(tree/fish) and your minimap will point you toward the location. Just like normal nodes, they have a fairly specific spot that they appear in and you gather from them just like you would any other node.

Added note: If you buy one of these early in an expansion cycle(for instance, you buy a lvl 90 folklore book for miner in january) then when they add new materials later in the expansion you automatically get them updated on your list for having already bought the book.