Gothic 3 Question about unnamed mage chests

Does anyone know where the mage chest is in the Hammer Clan mine (the big one filled with about 100 orcs if you include the tunnel and camp)? I've explored it twice and I can't find any chests. Apparently, there's a mage chest there.

Right next to Achmed. Sorry, sorry...couldn't help it.

World of Gothic is your best friend here, about as comprehensive info as you'll find for it.