Can't recall the sigil, but it's the one in Ravenscar that goes up to the glacial wastelands. Both my husband & I went to it and it did the glow thing that says it's active. We grabbed the glacial water and went over to use it to go back to Hrafn, and neither of us gets the chance to interact with it. We logged out completely and logged back in a good 15 minutes later; still no joy. Running back down to Hrafn (or whatever his name is) and checking, the stone claims to be active but doesn't let either of us use it. Went back up to the wastelands and it claims to be active there and still doesn't offer the x to interact statement.
I know the wretched thing worked before -- four of my six wizards have used it. Is this a new glitch or just some weird one-off? All other interact-able areas allow interaction. Neither end of this teleport stone set does. While I don't particularly mind having to mark a teleport spot every time I go up there, it does rather become a bit of a mana drain.