When they first came out you could only use the stone once per day. That made moving a whole set of skills from one player to another very time consuming. And a bit of a puzzle if you were trying to move multiple skills between 2-3 characters and only had 2 stones.
Now any character on that account can claim the skill, even the one who placed the skill in the stone in the first place.
The only restrictions are:
If you recently exited combat. You have to wait the same time it takes when logging out.
Have a character engaged in a New Player quest from New Haven.
It is a great way to build 1 skill and share it between 2 characters. Like if you have a mage tamer and an archer tamer, but don't want to raise taming up twice. Switching out the taming skill is quick.
I actually run a Sampire Archer who has also raised swordsmanship. I stone off Swords and parry for Archery and Healing, depending on what I am fighting.
