I sent another email. I will update!If it were mixed with a Lavender Marans, it would just be a plain black chick.Lavender just dilutes black and two copies are required to have any visual effect. Any chick from a mix of Marans would look black and carry one copy of a hidden lavender gene! I would be very curious what their thoughts are! She did definitely look like a Barnevelder when young so I see why they said that
Based on the photo below (left) I think you’re right. I haven’t learned much about chicken genetics yet but she definitely seems to be showing the silver duck wing coloring. This is so coolIf it were mixed with a Lavender Marans, it would just be a plain black chick.
This was the response I got via email… not very helpful!If it were mixed with a Lavender Marans, it would just be a plain black chick.
Somebody hopped the fence then and she's a cross.
Pure Barnevelders with yellow legs wouldn't throw offspring with slate legs. It's not an Isbar. They're only blue, black, or splash or possibly birchen. It's interesting they won't admit to that because they don't have any breeds that remotely make sense if she was pure. 
Now that's interesting. I've heard apparently Denizli Longcrower hens quack but they're not carried by your breeder. They also look more similar. I wonder if they carry them but they aren't for sale. Huge stretch but the quaking is an interesting similarity. Here's a link to their noises.
I will have to find pictures of them as chicks! She does sound quite similar to them and the looks are similar but so far her comb is much smaller
Her comb will get larger with age. She's not sexually mature. Since they're more of a landrace breed bred for the trait of crowing, chick down and adult color will vary and won't be standardized. I wouldn't focus too much on chick down personally. Do you have any updated pictures?
