QTR-Quadtone RIP

I asked this question on the DigitalB&WPrint group, which I would have
thought was the more appropriate group, but got no responses, so am
trying here.

I've bought some bulk Image Specialists K3-equivalent ink, but not
from MIS. It was a 9 ink set, and so included both MK and PK. What I
was wondering was whether the MK is likely to be the "Eboni" ink that
is so often mentioned here, or is this an MIS-only ink? I am assuming
that as both MK and PK are included in the set, that it's not the
"universal" K that MIS also sell. So the question is: is "Eboni" an
Image Specialists ink?  Does anyone know?

Ferdinand