> Ravens have an iridescent sheen to one side of their feathers that refracts
> light and at certain angles reflects blue, green and violet, but very little
> red, yellow and orange. This can also be seen on the dark feathers of some
> species of ducks. Black cat-hair, on the other hand, can reflect all of the
> colors of the rainbow equally well.

Haraldr konungr kvað:

Fram göngum vér
í fylkingu
brynjulausir
und blár eggjar.
Hjálmar skína
hef-k-at mína
nú liggr skrúð várt
at skipum niðri.

Forward we walk
in formation
without byrnies
under "blue" edges.
Helmets shine
I haven't got mine (byrnie)
now our equipment lies
down by the ships.

(Pop quiz: How do we know 'mína' refers to 'brynju'
rather than 'hjálm'.)

So what colours does a blade reflect? :-)

> If the Old Norse experience of the color 'Black' was culturally influenced
> by ravens, then that could also help explain the relationship. It would be
> near impossible to prove, however, and I'm not trying to do so.

Interesting idea, though I, like you, don't have
anything to back it up with :-) Some scholar wrote
a treatise on the use of colour in the Eddaic poems.
I don't remember the specifics but it might be interesting
to get a hold on.

Kveðja,
Haukur