A rapid light polish with the bend of the burnisher across a gold stem will give a very good finish (c, fig. [108]).
Properly burnished gold in a right light is at first as bright as a mirror, and in some lights may look [p161] quite dark by reason of its smoothness. A piece of white paper may be held at such an angle that the white light from it is reflected by the gold; this will show the quality of the burnish, and also show up any brown spots which the leaf may have failed to cover. It is helpful, moreover, during the actual process of burnishing to have a reflecting paper folded and standing beside the work (fig. [111]).
At first the size under the burnished gold is not thoroughly hardened, and great care should be taken of it (not to breathe on nor finger the gold in any way, nor allow it to lie about and get dusty). It is best to put it away safely in a drawer for a week or two.
After a week or fortnight, when the size has set a little more, it may be very gently re-burnished, and this may be done again at the end of another [p162] fortnight. This final burnishing, when the size is nearly hard, will give it a very lasting polish. It is well, however, to take every care of burnished gold, and to secure it from risk of damage as soon as may be. Illuminated miniatures were often protected by a piece of silk between the leaves—and this should be done now, in the case of fine work. That a bound volume protects the burnished gold within it is proved by the large number of MSS. in which the gold, laid and burnished 500 years ago, is in perfect and brilliant preservation.
REMEDYING FAULTS IN GILDING
To lay and burnish gold satisfactorily requires considerable experience. Careful practice with a good “size” will overcome the chief difficulties: these, and their probable causes, are here summarised:—
| To make the Size stick to the Surface. | Probable Causes of Size not sticking to Parchment or Paper. |
|---|---|
| Clean and pounce thoroughly: roughen if necessary (pp. [146], [167]). | Dirty Surface. |
| Greasy Surface. | |
| Horny Surface or | |
| Non-porous Surface. | |
Procure or make a proper composition, mix thoroughly always, and stir frequently when in use. If composition is at fault, add—
| Size not sticky enough |
| Size not tough enough (and crumbling off) | |
| Both causes due to faulty composition, or mixing. [p163] | |
| To make the Gold-leaf stick to the Size. | Probable Causes of Gold-leaf not sticking to Size. |
| Breathe on thoroughly and avoid delay in laying the gold (p.[154]). | Size not damped enough due to
|
| Do not allow size to dry too long (p.[151]). | |
| More, and more careful, rubbing and pressure (p.[156]). | Not sufficient rubbing and pressing on of gold. |
| (See above.) | Size not sticky enough. |
| Raise the size sufficiently (p.[150]). If not enough when dry, roughen surface and add another coat. | Not enough size, particularly in thin lines and edges. |
| Try re-gilding (p.[157]), or, if spots persist, scrape them gently and try again: failing that, gently scrape off all the gold and try white of egg (dilute), or a slight re-sizing (as above). | The gold may refuse to stick in spots with no apparent reason, but probably from one or other of the above causes. Or the size may have been touched accidentally and have become greasy or dirty. |
| If the spots are very small and there is not time to spare for re-gilding, they may be touched with powder gold and dilute white of egg, and burnished when dry. | |
| To make the Gold-leaf smooth and bright. | Probable Causes of Gold-leaf’s not burnishing properly. |
| a. Allow longer time (p.[151]). | Size too sticky. Due to—
|
| b. Allow longer time (p.[151]). | |
| c. Remove size and re-size with proper composition. | |
| Sometimes this difficulty may be overcome by using several coats of gold-leaf (p.[157]). | |
| Scrape smooth with sharp knife. (Sometimes the size itself isburnished before the gold-leaf is laid.) | Size rough surfaced. |
| Clean burnisher frequently. | Burnisher becoming dirty. |
- a. Sticky matter.
- b. Toughening matter