Manufacturing tecnuiques

The shells used for the realization of cameos are:
1. Cassis Madagarcarensis, so called ’sardonyx helmet’, about 30 cm high, chestnut-brown colour at the base and perfectly white on the entire surface to be engraved.
2. Cassis Rufa: so called ’ cornelian helmet’, about 16 cm high and it has a reddish layer inside, the exterior shows light colours.
3. Cassis cornuta: about 25 cm high, with an orange interior and a white exterior. Caught in Mozambique, Madagascar, Kenya and the Caribbean islands. The shells of the ’Cassis’ family are particularly suitable for carving because the two layers of colour are clearly distinguishable from each other and allow the figure to stand out.
4. Cypraea Tigris: also called ’tigrina’, about 5-10 cm high with 7 different layers of colour in the following order: a striped exterior, white, yellow, grey, blue, two shades of purple and finally a bluish white. Caught in the Indian and in the Pacific side.
5. Trombus Gigas: called ’ pink shell’, about 26 cm high, its white and pink layers are not always distinguishable from each other, also used for necklaces, buttons, etc.. Caught in the Bahamas.
Manufacturing stages

Preparation
1. Choice of the right shell for the job:
2. Scoppatura: it’s the cutting of the ’cup’ or superior part, the convex part of the shell. This operation was performed using a rotating disk jet of water and abrasive powder, now it is undertaken by a diamond blade.
3. Marking: the artist draws the shape of the cameo inside the shell cup.
4. Cutting: the shell is cut to pieces along the marked perimeter.
5. Improved shaping: Using an abrasive wheel the desired shape is modelled. It’s usually oval.
6. Fixing: the oval is fixed to a wooden stick called ’spindle’ through a warm mixture of colophony, beeswax and powdered chalk.
7. Roughing: using a small grinding wheel, it is possible to polish the outer layer to be carved.

Engraving
1. Design: the artist draws the subject on the shell surface:
2. Outline: Using a wide-tipped chisel we remove the white excess part of the figure revealing its volume.
3. Engraving: we keep on working with various measures of engravers in order to make the figure more and more defined and prominent.

Finishing touches
1. Finishing touches: we finish the engraving using a thin-tipped chisel.
2. Cleaning: once the cameo is removed from the spindle it’s rubbed with a pumice stone and oil to make the surface smooth.
3. First degreasing: the cameo is washed with soap and running water.
4. Polishing: the cameo is dipped in oil to highlight its sheen.
5. Degreasing: the final wash is with warm water and soap, then it is dried with a linen cloth.

Bulini
Conchiglia Tigre
Conchiglia Rosa
Corniola
Sardonica
Vitiello Cameos