It can be dismantled using a Hammer. Note: If dismantled under an active portal, the portal will not disappear but the Teleport Stone will be extremely difficult to pick up, since the player will usually enter the portal instead.
When the player uses a Rune of Teleportation, a portal is created where the player stands. The other portal will appear above an active Teleport Stone. Only one stone can be active at a time. The portal will stay open for 5 minutes, and can be made anywhere aside from NPC-built structures, like the Settlement. The portal can be used by standing near it and pressing the action key.