According to the NERD web site, both albino and granite are recessive mutant genes. This cross would produce

1/2 albinos that are heterozygous for granite
1/2 normal looking babies that are heterozygous for granite and heterozygous for albino

If you want granite albinos, you'd need to cross that granite to a burm that has both albino and granite mutant genes, as NERD did. Good luck.

Paul Hollander