I don't think those are blue chin aka squirrel, but rather black chin (which have a bluish surface color since visually the black hair is diluted by the interspersed pearl).
Honestly neither the first silver fur nor the fawn look like they have ring patterns to me.
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The first silver/gray fur (above) looks more like steel or maybe even silvering. Where on the body was this fur photo taken? And does this rabbit have agouti markings on its ears, eyes, muzzle and belly?
Most of the colors we're talking about have a slate gray undercolor, so that's not really unusual. I suppose it could just be an exceptionally bad ring pattern, but I cannot make out rings, rather it seems more like white hairs and silver tipping on some of the dark hairs. Silvers (and Silver Fox, and Champagne d'Argents to a certain extent) have a combination of white hairs and silver-tipped hairs among the black hairs. But if you want
it to look like rings, you can sometimes imagine you can see really messy ones. Unfortunately, I can't seem to find a good photographic example of what their fur looks like. My Champagnes are currently far too light in their surface color to be very good examples, but here is one anyway:
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Your fawn/red (below) looks pretty normal to me.
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I don't see rings per se, just surface color that isn't as deep running toward the skin as might be desired, and maybe a bit of smut. There does seem to be some fading on the tips in one part of the photo (upper left) which is interesting, but you're right, I don't see how you could have steel in a non-extension color. (But you could
Here are a couple of reds (a senior Mini Rex and a junior Satin). These are both nicely smut-free with deep-running color, but you can see some variations in the color along the length of the hair shaft in the mini rex:
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This is the only one that really looks like a chinchilla to me. Though not ideal, the bands are reasonably distinct, with the proper slate gray undercolor followed by a pearl intermediate ring. From the ARBA chinchilla Satin SOP: "Immediately above the intermediate ring color should be a narrow black band, followed by a layer of white guard hairs, and topped with black guard hairs."
However, I'd definitely be inclined to suspect wide band here. In general, the rings should be even in width
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But yours has a much wider intermediate band:
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Actually agoutis can have five to nine bands of color - "one or more
intermediate bands of pearl, alternating with shades of blue-gray." Most of my chins have had four to six bands (not including the ticking). And here's my friend's spectacular agouti angora with at least six bands:
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This is such an interesting discussion; thank you for posting these!