Resonance Crystals

Resonance Crystals were magical items developed by The Medallion Caravan Company, used to counteract the deadly Emissions which once blocked the route to Duloris. With the end of the emissions, it seems the resonance crystals are now relatively useless. 
=== Appearance ===
Resonance Crystals are bright red circular crystals, usually housed at the center of silver medallions. 
Whenever an emission is detected, the crystal begins flashing, and when an emission reaches the wearer, the send out a red wave of magic energy, protecting the user.
The Crystals have no known use aside from this.