Although it appears to be a normal pearl on a light chain, a Periapt Of Wisdom actually increases the possessor's wisdom score in the form of an enhancement bonus of +2, +4, or +6 (depending on the individual item).
Prerequisite: Craft Wondrous Item, Owl's Wisdom
Aura: Moderate Transmutation
Caster Level: 8th
Market Price: 4,000gp (+2); 16,000gp (+4); 36,000gp (+6)
Cost to Create:
Base Cost: 2,000gp (+2); 8,000gp (+4); 18,000gp (+6)
XP Cost: 1,000 (+2); 4,000 (+4); 9,000 (+6)
AC: 11
Hit Points: 1
Hardness: 1
Break DC: 6
Weight: -
Based on an entry in the Dungeon Master's Guide 3.5 Page 264