Ore Variants / Cave Lighting

With the new generation of veins for ores in Minecraft we need ore variations.

Variants of ores such as gold could be more common along cave walls, look much more like a blend between stone and the ore (maybe like you sprinkled it on top), they glisten and give off a faint light level and most importantly if they are mined they give small fractions of its original counterpart due to the abundance of it. These variants would also only generate on the walls of caves. 

This would be all around a great way to spunk of the caves tremendously without adding a new complex part of the game such as copper.