This transparent black crystal has a faint, sickly glow.

A crystal of life drinking bestows a small amount of life energy upon you each time you damage a living creature with the weapon to which the crystal is attached. Dealing nonlethal damage with the weapon doesn’t activate the crystal’s effect.
Each time you deal damage to a living creature with the weapon to which this crystal is attached, you heal 3 points of damage. When the crystal has healed a total of 30 points of damage, it becomes inert until the following day.

Prerequisites: Craft Magic Arms and Armor, vampiric touch.
Cost to Create: 500 gp (plus 500 gp for base item), 40 XP, 1 day.