MTF delves into the intricate art of cameo carving, a highlight of Cartier's Métiers d’Art Watch Collection 2013. This fifth installment of the series explores how Cartier revives ancient decorative techniques, specifically focusing on agate cameo carving. Readers will discover the historical significance and detailed process behind this exquisite craft.

Cartier Métiers d’Art Watch Collection 2013 part 5: Cameo Carving

Since Cartier decided to set up the Haute Horlogerie division, they have tried new techniques in both future technology and ancient skills to explore the possibilities of craftsmanship. On one hand, they are pushing the frontiers of mechanical engineering and on the other hand, they are reviving forgotten decorative arts like plique-à-jour enamelling, grisaille enamelling, straw marquetry, granulation and cameo.

 

In this fifth report of the techniques found in the Métiers d’Art Watch Collection, we will be looking at an ancient handcraft technique  – Agate Cameo Carving.

Agate as a Gemstone

Agate is a variety of chalcedony, a term for all cryptocrystalline quartzes (agate, petrified wood, onyx, bloodstone, jasper, carnelian, etc) It occurs in many colours and in all degrees of diaphaneity; although mainly opaque to translucent. There are many agate varieties named after specific locations or after a physical characteristic (moss agate). "Chalcedony" is likely derived from the name of an ancient town in the Bosphorus, Asia Minor.

Banded agate (also known as onyx), formed as layers of chalcedony, making it a perfect gemstone for glyptography as seen in cameos and intaglios. Cameo is a method of carving an object such as an engraved gem, item of jewellery or vessel. Usually the cameo is carved with the white layer in relief, while the intaglio design is carved into a darker layer to reveal the lighter layer below. Originally, cameo only referred to works where the relief image was of a contrasting colour to the background; this was achieved by carefully carving a piece of material with a flat plane where two contrasting colours met, removing all the first colour except for the image to leave a contrasting background.

The name agate is derived from the Achatus river in Sicily (now called Dirillo river) where large amounts of this gem were discovered as early as 300 BC. During the Gallic wars, agate deposits were discovered along the Nahe river (a tributary to the Rhine) in Germany. The gem-cutting facilities set up by the Romans still survive to present day and, although the deposits are now depleted, Idar-Oberstein - on the Nahe river - is still the major lapidary center of Europe. Today the agates cut there are imported from Brazil and other locations.

South American deposits are now the most important suppliers of agate that appear opaque grey in their native state. Dyeing brings out their colours and patterns. The art of dyeing is known from ancient Roman times but elevated to their zenith in Idar-Oberstein, Germany, after 1820. Inorganic dyes are more durable than organic dyes and the process is a commercial secret. Blue colouring is achieved with iron pigments. Agates are first placed in yellow potassium ferro-cyanide and later boiled in hydrous iron sulphate, producing "Berliner blue".

Cameo of a bust of Elizabeth I (1533-1603)
Creator: English (nationality).
Date: Cameo: c. 1575-85; Mount: early 1700s.
Materials: Sardonyx: brown and white; open gold mount with claw settings, suspension loop and ring.

Brooch with cameo of Queen Victoria
Creator: French (nationality)
Date: 1851
Jewelwork by Félix Dafrique; Cameo by Paul Lebas.
Shell, gold, enamel, emeralds and diamonds

Cameos in Antiquity

Cameos, valued since antiquity as engraved gems, were exceedingly popular during the Georgian and Victorian periods. Many different materials were used for carving cameos. For hardstone cameos, varieties of agate including onyx, sardonyx and jasper were popular. These stones, with layers of different colors, allowed for depth and nuance in the carvings. Other non-layered gemstones such as malachite, coral and amethyst were were fashioned into monochrome cameos.

The methods used for carving these two types of cameos were as vastly different as the materials themselves. Hardstone was cut on a specialty lathe with steel drills and wheels. Carvings using this process took months to complete. Shell cameos could be carved by hand with a burin or engraving tool, taking only days to complete. These less labour-intensive therefore less expensive shell cameos were popular with tourists looking for souvenirs.

A third technique, commesso, joined together layers of different materials such as hardstone, coral, and mother-of-pearl, was a French form of gem carving that resulted in a pictorial relief like mosaic, and not a true cameo.

Empress Josephine is credited with initiating the fashion for cameos. Antique gems from the royal treasury were set by her jeweller, Nitot, in the Crown of Charlemagne and in bracelets. A portrait of Josephine wearing cameo jewelry sparked a multinational trend. During the Restoration in France the fashion died out while in England the trend continued to build until Victorian times.

Cameo Carving

Many modern cameos are carved into layered agates. The layers are dyed to create strong colour contrasts. The most usual colours used for two-layer stones are white on black, white on blue, and white on red-brown. Three-layer stones are sometimes made. The colours are usually black on white on black.

The layers are translucent; this allows the artist to create shading effects by removing material to allow the background layer to show through. This way a very realistic, lifelike quality to a figure can be achieved. For example, thinning the top black layer on a three-layer stone changes its colour to shades of brown. Removing material from the white layer creates shades of blue or grey, depending on the colour of the base.

The majority of modern agate cameos are carved with the aid of the Ultrasonic Mill. This is a process where multiple copies of a master design can be produced very quickly by pressing a master die onto the agate cameo blank. A film of diamond slurry is used to aid cutting and the die vibrates ultrasonically in a vertical motion. The master is often hand carved by a skilled cameo artist. The result is a cameo that has a satin surface texture described as "freshly fallen snow". This texture and the lack of any undercutting are used by appraisers to prove that the cameo is machine-made.

Cartier Cameo Carving

Cartier has daringly restored the technique of cameo art to watchmaking. The highly delicate skill consists of bringing out all of the shades of a stone, from dark midnight blue to shimmering white without breaking it. The cameo creates relief and enhances the flash of light. It takes about 80 hours of work for producing this dial.

Cartier used a real agate stone with different colours. The traditional dyeing technique was employed to emphasize the colour, contrast and beauty of the dial.

The engraving process is the work of a Master engraver based in Switzerland. The preliminary, preparatory work on the stone is carried out using an ultrasonic milling machine. After that, the stone is entirely carved by hand.

Although the ultrasonic carving process is widely used for basic preparation of the stone, the milling tool attachment is itself hand-carved and engraved by the craftsman beforehand!

Rotonde Crocodile Cameo Tourbillon

Cartier combines an animal inspired art piece with a tourbillon in a special Rotonde Crocodile Cameo Tourbillon watch encased within a 40mm white gold case and limited to an exclusive production of 30 pieces. 

The dial is probably what sets is apart from all other art inspired timepieces as it features an almost life-like sculpture of a crocodile head in agate set on white gold.

Mechanical artistry is achieved by the off-centre flying tourbillon located just below the central indicators.
Visually striking, the Cartier Rotonde Crocodile Cameo tourbillon is equipped with an in-house caliber 9452MC bearing the Geneva Hallmark of excellence.
 
Paired with an alligator strap and matching gold deployment clasp, the watch is one that certainly represents a unique addition to the ever growing line-up from the fine jeweller turn watchmaker.

Case: 18-carat white gold with sapphire case back.
Crown: beaded crown set with a sapphire diamond.
Dial: 18-carat white gold with a crocodile motif in a cameo of natural agate.
Strap: black semi-matt alligator skin.
Buckle: double adjustable folding buckle in 18-carat white gold.
Water-resistance: 30 m / 100 ft / 3 bar.

Numbered limited edition of 30 pieces.

Manufacture mechanical movement with manual winding, calibre 9452 MC, certified Geneva Seal, flying tourbillon with seconds indicated by the tourbillon carriage in the form of a 'C'.

Cartier Métiers d’Art Series

Cartier Métiers d’Art part 1 - Grisaille Enamel: CLICK the following URL link:
cartier.watchprosite.com

Cartier Métiers d’Art part 2 - Miniature Painting and Plique-à-jour Enamel: CLICK the following URL link:
cartier.watchprosite.com

Cartier Métiers d’Art part 3 - Engraving and Champlevé Enamel:CLICK the following URL link:
cartier.watchprosite.com

Cartier Métiers d’Art part 4 - Gold Granulation: CLICK the following URL link:
cartier.watchprosite.com

Cartier Métiers d’Art part 5 - Agate Cameo Carving: CLICK the following URL link:
cartier.watchprosite.com

 

Dr M. Teillol-Foo (2013) PuristSPro