THE USE OF GOLD
Gilding, in illuminated work, is done with either gold-leaf or shell
gold. Gold-leaf is the metal that has been beaten out into thin sheets,
and shell gold the same ground up and mixed with gum and honey. Shell
gold is so called on account of the fact that it is sold in small
shells ready for use.
The student is especially warned against using any of the varieties of
gold paint for work that is desired to be permanent. These are mixed up
with powdered bronze, and, in course of time, will turn black.
Shell gold is painted on in the same way that other colours are.
A small brush should be used, so as not to waste any more than is
absolutely necessary. It is also essential that quite clean water
should be used, to ensure the gold being as bright as possible, as if
the water is contaminated with colour it will dull the gold when mixed
with it. The great disadvantages of shell gold are lack of brilliance
and also the expense. It is, however, very useful for putting in very
fine lines, which are difficult when using gold-leaf.
The use of gold-leaf for gilding purposes has been known since quite
an early period. Some of the early manuscripts were written with gold
and silver letters on purple vellum. Silver-leaf is prepared in a
similar manner to gold-leaf; unfortunately, however, it quickly turns
black when exposed to the air. The best substitute for silver-leaf is
undoubtedly platinum, although it is very expensive. Aluminium leaf is
sometimes used, but it is rather too thick for fine work. Sometimes
aluminium paint is used where silver work is required. This, however,
has the same objection as shell gold in lacking brilliance.
Without a doubt the use of leaf, raised and burnished, is the ideal
method of gilding. If the student examines any of the old MSS. of the
best periods he is bound to be struck with the brilliance of the raised
gold, and he will notice how superior are the results to any produced
by means of gold paint. Gold-leaf gilding, even if it is unburnished,
is infinitely more brilliant than either gold paint or shell gold.
Some difficulty may at first be experienced in handling the leaf, as,
being so thin, it has an unpleasant habit of blowing about. It is sold
in books containing twenty-five leaves. It is best to get that known
as “double fine gold,” specially prepared for illuminating. For large
masses of gold, a thicker leaf may be used, known as “quadruple.”
The student should be careful to use only the best gold-leaf. Some of
the cheap foreign leaf is very poor in quality. He should be careful
also to avoid the leaf known as “Dutch metal,” which is not gold at all.
A gilder’s cushion should be obtained with a knife and tip. (See Fig.
30.) The cushion is generally about nine inches by six in size, and
is made by stretching a piece of soft leather over a piece of board
slightly padded. A piece of parchment is fastened on one end, which
acts as a shield to prevent currents of air from blowing the leaf
about. The student should be extremely careful to prevent touching
the surface of the cushion with his fingers, as, if it becomes greasy
in the slightest degree, he will experience trouble through the leaf
sticking to it.
[Illustration:
Guilder’s Cushion
Guilder’s Tiip
Agate Burnisher
Guilder’s Knife
Camel Hair Mop
FIG. 30.]
The best way for the beginner to learn how to handle the gold-leaf is
to get an experienced gilder to show him how to use the cushion. If
this is not possible he ought, by carefully following the directions
given here, to be able to manage the leaf after a little practice.
The best way is to take the book of gold-leaf and open it very
carefully. It is then turned over so that the leaf rests on the
cushion. The back of the book is then gently tapped with the
finger-tips; if it is then carefully lifted up the leaf will be found
lying upon the surface of the cushion. If it is not lying quite flat
and even, it may easily be smoothed by blowing gently on the centre of
it. It is as well, however, not to be too vigorous, or the result may
be to crumple the leaf up worse than before.
The student should be careful not to touch the leaf with his fingers,
otherwise it will stick to them and the whole leaf will probably be
spoiled. He should also avoid breathing upon the surface of the leaf,
or it will probably roll up in a hopeless tangle, or else go floating
off into the air, as the slightest puff of wind tends to do this.
It is hardly necessary to point out that it is not wise to attempt
handling gold-leaf for the first time with the doors and windows open,
as the slightest draught will carry the leaf with it.
The gilder’s knife must not be sharpened, as, if this is done, the
result will be that instead of cutting the leaf it will probably tear
it and cut the cushion. One important thing to remember is that the
fingers should be kept from touching the blade, otherwise the leaf
will stick to it owing to the slight amount of grease left on it. Also
if the blade is allowed to get rusty it is liable to tear the leaf
instead of cutting it properly. The knife should be kept clean, and the
edge should occasionally be burnished with the back of a pen-knife, or
something similar, to remove any roughness that may prevent it from
giving a clean cut. If it is found that the leaf sticks to the blade of
the knife, it is because there is a slight amount of grease on it; this
may be removed by rubbing the knife on a board with a little powdered
bath brick.
The leaf is cut by placing the knife carefully down on to the surface
of the leaf, and moving it backwards and forwards with a sawing
movement. The knife should be pressed down firmly on the cushion when
cutting, and great care should be taken not to rumple the leaf in so
doing.
It is as well not to endeavour to be too economical when cutting the
leaf up. A piece of leaf should be cut large enough to cover the part
that it is required to gild. If the student tries to be too exact in
cutting, he is very liable to cut the piece too small, and then other
pieces have to be cut to patch the parts not covered with the leaf.
When this is the case, apart from the extra time taken up, it is false
economy, as more leaf is required than if a slightly larger piece was
cut at first.
After the leaf is cut, it is conveyed from the cushion to the work by
means of the gilder’s tip. (See Fig. 30.) This is a kind of brush made
by fixing a thin layer of hair between two pieces of card, which are
pasted or glued together. This tip is used by first rubbing it on the
skin or hair, and then placing it on the piece of leaf, which will
then adhere to it. It can then be carried and placed in position where
it is needed. The reason that the gold adheres to the tip is because
by rubbing it on the skin or hair the tip becomes slightly greasy and
attracts the leaf.
If any leaf is left on the cushion after finishing the gilding, it
should be carefully replaced in the book. This may be done by putting
the top of the blade of the knife down flat on the cushion and pushing
it under the centre of the leaf. By this means the leaf may be lifted
and carried to the book. The tip should not be used for this purpose,
or some difficulty may be experienced in inducing the leaf to leave
this for the book. When pushing the knife under the leaf, however, it
should be pressed firmly on the cushion, otherwise the result will be
to crumple the leaf and spoil it.
For dusting the loose leaf away after gilding, a large camel-hair mop
similar to that shown in Fig. 30 is useful.
For burnishing the gold, an agate burnisher is required. The best shape
is shown in Fig. 30.
For commercial work it is hardly worth while using gold-leaf, and
bronze powder is recommended instead. A method of using this will be
explained later when dealing with commercial work.