Don’t want to sound like a know it all negative Nancy but I don’t believe that’s an Isbar. I’ll toss up some pics of mine. Granted they don’t have a standard and I’m no expert but they come in blue black and splash. First pic is 4 blacks and a blue green fire Isbar. Second pic is one of each first import Isbar line from wabi sabi acres. Third picture is the closest resemblance to your chick I could find. Like I said I’m no where knowledgeable as some others on here, but it looks like something else to me. Still a great looking bird.
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I do see some resemblance and could feather out and I be wrong. So just think of this as a suggestion not me saying they aren’t what you say they are.