A Few Montporte Magic Items

I have decided to make each magic item in the Montporte Dungeon unique, with the exceptions of scrolls and potions. I am not worrying about back story, since the players won't be concerned either. While I actually need to spend some time doing this (maybe with random tables), I have created some items and the players have found a few. Here is what they have found so far:

Lens of Melnar: A convex glass lens with a brass frame and handle (betraying its Gnomic origins). The Lens of Melnar can perform a Detect Magic spell twice per day. It can also identify potions at will. This second ability is successful when the user rolls below his/her intelligence on a d20. Wizards gain a +3 bonus on the roll; Sorcerers, illusionists and druids, a +2 bonus; Clerics and thieves gain a +1 bonus.

Mace of Curm: This mace is +1 to attack and damage against all foes except elves and kobolds, against whom it provides a +2 bonus to attack and damage. The Mace of Curm also allows the wielder to Detect Undead three times per day.