This dun and ecru diamond is incredibly durable.

An iron ward diamond lends its toughness to armor, helping it absorb blows in combat.
The least version of this augment crystal grants you damage reduction 1/—. This damage reduction stacks with similar damage reduction granted by any other source. Once the clasp has prevented a total of 10 points of damage, it becomes inert until the following day.

Prerequisites: Craft Magic Arms and Armor, stoneskin.
Cost to Create: 250 gp, 20 XP, 1 day.