Holly, in France wrote:

marks or would have to be planed and sanded. We replaced a big oak
beam
in a house last week where the joists were still in good condition.
The
joists are black since the room was originally used as a forge. The
new
beam sticks out like a sore thumb! When the oak floor is down we will
sandblast the whole lot, including the underside of the floorboards.
There will still be a difference in colour but overall the effect
will
be more uniform. One thought though, I wonder if this would be
suitable
for furniture since the rough surface would be prone to collecting
dust,
making it harder to clean.

would suggest talking to these people before going ahead.
http://www.periodproperty.co.uk/cgi-...sing/forum2.pl

NT