Gold
leaves are fairly expensive. Each book of 25 leaves 80mm by 80mm costs
between 80p to £1.25 (1972). There is a much cheaper substitute
called "Dutch leaf" in the trade and these are sold in larger
books 140mm square and cost about 50p each. They are copper leaves
which are coated with gold by the action of zinc fumes. The method
of application is the same as for gold leaf and it is very difficult
to notice the difference. A few months after application, Dutch (or
Schlag) leaf tends to darken if it is not protected with a coat of
colourless lacquer or polyurethane varnish. In any case, the finished
result is vastly superior to what may be achieved with spraying gold
paint from an aerosol container.
Real
gold or Dutch gold will make a really professional job, but we do
not recommend the use of loose gold leaf or loose Dutch leaf if you
have no previous experience of gilding. Transfer gold is very easy
to apply, as the leaves can be handled and pressed on with the fingers
on the tacky gold size. A good tool for the job is what the gilders
call a "bob", which consists of a round pad of chamois leather
filled with cotton wool, used to settle the gold leaf in its final
position. When the area to be gilded has been covered with gold, any
little areas left uncovered can be filled with left over offcuts.
The
final smoothing down is best done with a silk cloth, 24 hours after
the application of the gold leaf, when the size is in its final stage
of hardening. The smoothing down is best described as a half-patting,
half-stroking motion, the aim being to create a perfectly even and
smooth skin of gold. When you are gilding small areas within a painting,
such as may happen on the soundboard, it is not essential to have
a gesso foundation under the gold size, but the wood grain must be
filled somehow. Therefore, apply a thin coat of shellac to the part
to be gilded, and when dry, rub with flour glasspaper, twice. Now
you may apply the French gold size to the small areas and proceed
as previously described.
