Granite

Granite is a marking that blankets large swaths of the horse's body in a heavily roaned texture that extends vertically across the body in a manner similar to Tobiano. 

Granite cannot cover more than 80% of the body, and it will be hard-edged and does not fade out like roan. At minimum, it should cover about 25% of the body.

This gene is only available through breeding and cannot be used on semi customs.

The geno code for Granite is written as:
nGn or GnGn