Tuesday, January 17, 2012

The difference between the bone, ivory and celluloid

Ivory

Westerners loved figures carved in elephant ivory. The elephant tusk is formed of dentine containing inumerable tubes filled with wax running the whole length. It is this wax that gives objects their polish. Another way to distinguish ivory is by looking closely at the lines within it. Cut along the tusk, these can be seen as light and dark lines. Cut through a cross-section, radiating lines crossing each other and making minuscule diamonds are visible.


Most ivory figures are carved from a single piece except, perhaps, for a stick or the base. In the centre of the bottom of the carving will be a hole that was the nerve canal. This is frequently plugged by a red lacquer signature reserve, so do many poor ones - they are not a sure guide to quality. Price is closely linked to size. Some figures of 5½ inch in tall could be worth around £300, while the best Tokyo School carvings can make as much as £30,000.


There is a popular misconception that ivory goes brown with age. It doesn't, although strong sunlight may cause browning or bleaching.

Bone

Bone, unlike ivory, is a "live" material and is a powerhouse of the body. Within the thin shell is a hollow containing a sponge-like material. Blood flows through bones and appears on the outside as black/brown dots or short lines. It is impossible to carve this away and they are the best clue that the piece is bone. Even when using large bones such as those of buffalo, only relatively short pieces can be obtained due to the form of the material. Therefore, most bone figures are sectional, small pieces held together with pegs and fish glue. After a century, the glue is breaking down and many figures are coming adrift. They are not worth giving to the restorer to repair but it can be done carefully by anyone. Most figures are poorly proportioned and with minimal engraving, as bone is much harder than ivory. Bone pieces are readily available and will make £5 - £100, depending on complexity.


Celluloid (Plastic)

If you closely looking at celluloid figures you will  notice that the colour is very similar to ivory, and there are lines that appears on the surface, much look like an ivory. But also you will notice that the lines are too wide and regular to be the real thing.


The best test for any plastic (modern resin copies are a current problem) is to place the piece on the cheek; plastic will be warm, while ivory and the bone will be cold. The mark could exist on the base, and it could be the maker, wholesaler, retailer or even a sponsor of the maker.
While there are collectors of celluloid - some pieces are very good substitutes - prices are always far lower than the ivory. Typically, the brooch might cost a few pounds, while a treasure ship might be nearer £50.




















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