I read with interest Nicolas Simons comment about keeping ivory keys
white and how light affects them.  I live in the far west of Cornwall
in the UK.  The area is famous internationally for its artists colonies
in Newlyn and St. Ives, and the reason given for the artists coming to
the area is the quality of the light.

When I was young -- too many years ago! -- in the town of St. Ives,
right on the outskirts, you would see a large number of greenhouses or
glass houses.  Many people thought they would for growing fruit of
tomatoes.  How wrong they were!  The buildings were, along with the
other buildings on the site, making ivories for piano makers all over
the world including Steinway.  Once they had been cut they were laid
out on long benches to literally bleach them white.

So if the makers did it that way Nicholas is totally right about
leaving the keyboard open and in the light.  I suppose using a special
ultra-violet light bulb would do the same?

Obviously, celluloid and other types of key coverings not of modern
plastic also discolour, and in those cases it is not possible to clean
them or bleach them in a similar way to ivory.

I always keep all ivory key coverings that come off wrecked pianos of
where I have put on plastic, as you never know when you might need one.

Bleaching ivory white is obviously not the same as cleaning the keys
and I use a buffing wheel and paste to clean ivory keys, but that just
polishes and does not turn brown discoloured ivories to white.

Jonathan Holmes
Penzance, UK