CHAPTER XVI

THE GILDING METHODS OF THE MIDDLE AGES

The most casual observer cannot fail to notice the gilding that is such a prominent feature of the MSS. of the mediæval period. Brightly burnished gold, which appears as if it had been laid and burnished quite recently, although centuries have passed since the work was completed, cannot fail to impress and arouse one’s curiosity as to the gilding methods employed when this work was produced.

Some of the old MSS. that treat of painting and the preparation of colours give also some information concerning the various methods of gilding, and our knowledge of these methods is chiefly derived from these MSS.

Dr. A. P. Laurie has made careful examination of the different forms of gilding employed in illuminated MSS., and in his book, “Pigments and Mediums of the Old Masters” says that gold was used in three distinct forms: as gold-leaf laid on the surface, and in the form of gold paint, prepared by grinding leaf-gold to powder; the other method seems to have been a paint made of rounded granules of gold. He suggests that this gold was probably obtained from river washings, and that the only preparation has been to sift out the finer grains. He says, further, that when it is examined under the microscope this form of gold paint is easily distinguished from that prepared from leaf-gold, which presents the appearance of little particles of gold with sharp corners and edges, while this shows rounded granules.

The art of gold-beating is of very great antiquity. Pliny, in his “Natural History,” states that one ounce of gold was made into 750 leaves, each leaf being four fingers square. This is about three times as thick as the ordinary gold-leaf of the present day. It is very difficult to form any idea as to when and where it originated. Some think that it arose amongst Oriental peoples. It certainly has been practised amongst these since quite remote periods. Some of the coffins of the Egyptian mummies have gilding on them evidently done with gold-leaf in a similar way to modern methods. Some of the books of gold-leaf used by the ancient Egyptians are in existence to-day, there being one at the Louvre in Paris.

Pliny says, “Gold-leaf is laid over marble, etc., with white of egg, on wood with glue properly composed; they call it leucophoron.” In another place he states that leucophoron is composed of sinopia (a red earth colour), light sil (yellow ochre), and melinum (a white earth). Evidently this was mixed with size to form a ground upon which to lay the leaf.

The Lucca MS., of the eighth century, gives instructions how to prepare gold for writing by reducing the metal to a fine powder to form a gold paint.

The following recipe is from the “Mappæ Clavicula,” a MS. of the twelfth century: “If you wish to write in gold, take powder of gold and moisten it with size, made from the very same parchment on which you have to write; and with the gold and size near to the fire; and, when the writing shall be dry, burnish with a very smooth stone, or with the tooth of a wild boar. Item, if then you wish to make a robe or a picture, you may apply gold to the parchment, as I have above directed, and shade with ink or with indigo, and heighten with orpiment.”

Parchment size is prepared by boiling parchment or vellum cuttings with just enough water to cover them for about two hours. The size is then poured off and sets in a firm jelly when quite cold. When required for use a small portion is placed in a jar, which is put into a basin of hot water, the size then quickly becoming liquid.

In the writings of Theophilus, of about the same period, he gives a good deal of information concerning the mediæval methods of gilding. In