Color and pattern male

Head: silvery white.

Neck: hackle glossy vivid silvery-white; front of the neck similar to the breast.

Back, shoulders, wing-bows, saddle-hackle and breast: glossy silvery-white.

Wing-bars: silvery-white, inner-web faintly black transverse pencilled.

Primary-flights: inner-web black, outer-web silvery-white.

Secondary-flights: inner-web silvery-white black transverse pencilled, outer-web silvery-white except the tip where the pencilling continues.

Tail: main-feathers black; sickles and coverts green-glossy black with a narrow, sharply defined silvery-white lacing.

Breast,flanks, thighs and belly: silvery-white, flanks show some black pencilling.

Fluff: blackish-grey.

Down: light-grey.

Note 

Hen-feathered males correspond entirely in color and pattern females.

Serious faults

Yellowish tinge in hackles. Rust on shoulders. Black specks on breast, belly, thighs, and wing coverts. Too broad or very irregular lacing of sickles or tail-coverts. Absence of  sickle-lacing. 

Faults

Serious faults to a lesser degree. 

Color and pattern female

Head: silvery-white.

Neck: hackle silvery-white, some penciling allowed at base of the hackle; front of the neck similar to the breast, but slightly less strongly pencilled .

Back: silvery-white, each feather with green-glossy black fine straight tranverse pencilling, slightly wider than those of silvery-white.

Shoulders, wing-coverts and saddle: glossy silvery-white, each feather with green-glossy black fine straight tranverse pencilling, approximately as wide as those of silvery-white. 

Wing-flights: silvery-white, with straight green-glossy black tranverse pencilling, slightly wider than as those of silvery-white.

Tail: main-feathers and coverts silvery-white, each feather with green-glossy black fairly finely and straight transverse pencilling, slightly wider than as those of silvery-white.

Breast, flanks and thighs: similar to the shoulders, pencilling on the breast should retain as much as possible towards the top and not fade out too strongly.

Belly and fluff: silvery-white with black pencilling or peppering.

Down: light-grey.

Serious faults

Yellowish tint in the ground-color. Coarse or very irregular penciling. Insufficient color-depth and sharpness of the penciling. Insufficient penciling on the breast. Penciling extending too high up the neck-hackle.

Faults

Serious faults to a lesser degree. Ground-color in the penciling.

Genetic code: https://kippenjungle.nl/Overzicht.htm

Website from Henk Meijers with all available information regarding chicken genetics including the world famous 

Chicken Color Calculator

If hen-feathered Hf/Hf male it's on E^R