Fighting Fantasy Portal - Where's the Sapphire in Deathtrap Dungeon?
In the original Fighting Fantasy book, the sapphire is in the pipe along with the box (where the copper key is). In the mobile version by Nomad and Asmodee. it's not there.
Where's the (damned) sapphire?
It's after the rolling boulder trap (go north when you come to the door with the X). You have to pass 2 Luck checks in order to find the sapphire, so you will need really good Luck or the 4 Leaf Clover item.