This sounds like a finishing oil such as Deftoil and/or Watco.  We use
these at the Ross King Co. (pipe organ builders) to finish organ cases.
The application is easier than any other kind of finish.  It soaks into
the wood and hardens, rather than a film on top of the wood.  You can rub
the wet oil with 220 grit and the sanding dust will fill the grain (open
grain woods like oak or walnut) -- results are fabulous!  Repairing
scratches is as simple as dabbing some more finish onto the scuff and
wiping.

I have used Deftoil in my restoration of reed organs and feel it can't be
beaten for appearance and ease of use.  It's not as hard as polyurethane,
but the beauty of the wood isn't buried under plastic!  By the way, I do
not own stock in the aforementioned companies.  ;-)

Regards,¶
Robert Linnstaedt (Linnstaedt@aol.com)