Which are pure blood bielefelders?

[hazerbaker]

Hi,

This chicks' father is a bielefelder. Mothers are biel or rir.

Can we distinguish which are pure biel and which are biel-rir crossbred?

Thank you in advance.

 

[Sally PB]

@BlueBaby, can you tell?

 

[hazerbaker]

@BlueBaby didn't like my chicks i think

2 days passed. Still need answers please.

Adding a new picture.