Philosopher's Cache?

[Rulizen]

What do I do with this? I got it from Dumpster Dive.

[Iridescent Rainstorm]

It will have an alchemy component in it. You can use it to create new items using a formula.

[Chaosfox8888]

Actually, the Philosopher's Cache will give you a more specific kind of Philosopher's Cache. (Ruby, Sapphire, Emerald, Diamond, Gold, Platinum, etc.)

And you can open that one to choose a component.
Trust me, I've opened thousands of them.

[~ Aki - Fairy ~]

You can open it for a coloured cache (contain alchemy components) or charm (for that new GO-Fusion thing) - completely random what you'll get, or you can sell it as is.

Personally, I wait until I have a bunch and then open them up and sell the coloured caches or journey over to Item Alchemy Exchange and see who's buying what to sell via trades, possibly opening them to components (often sell for more than the coloured caches).