Dragonshards

Among Eberron’s most important resources are the three varieties of dragonshards: the fallenshards of Siberys, the crystals found in the soil of Eberron , and those drawn from the depths of Khyber.
All dragonshards appear as translucent rock or crystal with swirling veins of color suspended within them. The shape of these veins suggests the swirls of dragonmarks, though no one has ever found a shard that exactly mirrored a mark. The color moves and pulses within the translucent crystal, making dragonshards look almost alive and lending their color to the overall appearance of the crystal.