Enamel has been the top decorative techniques since ancient time in Geneva. Nowadays enamel produced in the area gains it&Zinc clad steel ground rod39;s a reputation from all over the world. In the period of the early 17th century to the late 19th century, enamel had been applied to decorate the case and plate of the watch, it can be said in some degree that the never deterioration and degradation property can bring this object on the list of “eternal” substances.
Here is an introduction on four steps of the producing process of enamel.
The raw material of the enamel glaze is flaky or rough powder. The raw material is placed on the mortar which is made of agate to be rammed into fine powder and then wash # away other mixed materials; degree of the purity and cleanliness of the enamel glaze will finally determine the quality of the finished product, dip suitable amounts of drops of nitric acid to completely dissolve any kind of impurity that could possibly affect the purity of the glaze. You will get purified glaze by via of this process and then save it in distilled water for alternation.
The selection of appropriate metal to be taken as primary matrix of work piece is very important in that enamel can only be affiliated to the surface of gold, silver and copper. Some jewelry manufacturer that pursuing excellence would take advantage of pure gold model, no exception would be allowed, such as the top jewelry brand Paiget. The matrix is required of absolutely cleanness, thus it should be immersed and cleaned in the sulfuric acid solution.
According to the different thickness of the pure gold matrix, a layer of counter-enamel must be coated in ahead, which is very important to keep the skeleton from being melted and deformation in the firing process. The succeeding process is that enamel master would lay the glue and glaze into the body with fine brush, then out the semi-finished products into kiln.
Only within the temperature that is higher than 800 degrees centigrade can the objects be melted, once it below the standard, enamel would be melted in a very short time (about 46 to 60 seconds). Once become liquid, it would be bonded with the metal matrix. Due to the reason that the size of the main role would be reduced, thus several more filler and firing would be manipulated to let the color achieve the best standard in the follow-up works.
Smoothing and Glazing
After the completion of the baking process, the smooth of the baked object would not that smooth on the surface, thus grading stone and water would be necessitates to keep the layer smooth, while the smoothing process would be lead to the atomization of the surface, so one more time to have a baking would be conducted soon to bring back the bright surface.
The above are the four main processes of the grand feu techniques: when mixed up with two kinds of metal oxide, two different kinds of enamel would be produced, one is the opaque, and the other is transparent. The latter can be applied to cover the hand-made engine-turned (or guilloche) or the gold engraved metal case and bottom cover; the decorative technique can combine the technique with the object to provide a vast changeable decorative effect by taking advantage of different types of enamel.
There are still some other detailed techniques of producing exquisite enamel product – CLOISONNE and CHAMPLEVE, which can take the Piaget Altiplano 38mm and Piaget polo as examples respectively. Techniques of the decorative property of the fine object still gained large development, such as the grisaille technique, which has brought great surprises for area of jewelry and watch making.