Hematite

Hematite was an ornamental stone that was favored by fighters.

Description
When polished, hematite was a shiny gray-black stone. It was often tumbled to make beads or cut in a baguette fashion (rectangular with beveled sides).

Powers
Hematite was not magical itself, but it was responsive to enchantments related to blood and life force and was used in necromancy and the healing arts. Specifically, it was used to create magical periapts for healing and foul rotting. A typical stone had a base value of 10 gp.

Only a handful of people (mostly powerful mages that kept the secret to themselves) knew that this common stone was one of the "nine secrets"&mdash;minerals that could be enchanted to become ioun stones.