[cnahr]

That was the first and only one I had seen, too. I suppose there may be a few more but they certainly seem to be rare. This exhibition had no other examples. The helmet with a flame-engulfed dragon that was shown mounted on an armor suit comes closest.

[thaumasiotes]

Armor 1 and Armor 3 both feature heavy use of a light bluish thread for decoration. In China a similar blue, made from kingfisher feathers, would be an imperial symbol -- do you know if there's any relationship / what the significance in Japan was?

[cnahr]

I’m not aware of any such relationship in Japan. The exhibition didn’t mention it, and I haven’t heard of it elsewhere either. I think it’s just decorative here.