Digital BW, The Print

>I'm wondering if this is true BO and the black ink is that cool, or 
>whether some color ink is mixed in...can you tell with a loupe?

As far as I can tell there are no colors being used in monochrome 
printing. The only loupe I can find around here is a 5X (can't find 
my 8X, where the heck did I put it?) and I couldn't see any other 
color with that. Also stopped a small print half way thru printing to 
check out the ink gradient as it was being laid down and saw no other 
colors.