How can celluloid be distinguished from real jet?

Several tests. Weight: celluloid is markedly lighter than jet - perceptibly “hollower” at the same size. Behaviour under warmth: celluloid warms quickly under friction and gives off a faintly aromatic smell of camphor; jet stays cool. Hot needle (a destructive test): a briefly heated needle sinks into celluloid and leaves a distinct smell of plastic; on jet it hisses without any characteristic odour. Fracture behaviour: celluloid breaks into splinters, jet more powderily. UV test: old celluloid often fluoresces yellow-green under UV light; jet does not.

Was celluloid mourning jewellery cheap or high-quality?

Clearly cheap. Around 1890, a celluloid mourning brooch cost roughly a tenth of a comparable Whitby jet piece. Celluloid mourning jewellery was the material of the lower middle class and the working class - groups who could not afford genuine mourning jewellery but were nonetheless obliged to wear dark jewellery under the strict Victorian mourning dress code (see The Middle Classes and Mourning Jewellery in the Nineteenth Century). The pieces were made industrially in large quantities in Birmingham, Pforzheim and Paris - by the million each year at the height of production.

Is celluloid safe to wear or to store?

With qualifications. Celluloid is highly flammable - the historical safety scandal around celluloid cinema film demonstrated that dramatically. Celluloid jewellery carries a lower fire risk, but should be kept away from open flames and sources of heat. Decay over time: celluloid degrades chemically across the decades - old pieces become brittle, discolour to yellow-brown and give off nitrogen oxides. These decay products can damage other jewellery and packaging. Antique celluloid pieces should therefore be stored separately, ideally in breathable paper boxes. For modern mourning use, celluloid is not advisable today - safer modern plastics and natural materials are available.

Celluloid (Mourning-Jewellery Imitation)

Celluloid is the first industrially produced plastic in history (1869) and became, in the late nineteenth century, the cheap imitation of jet, ivory and amber in the mass mourning jewellery of the late Victorian middle and working classes - the first “democratisation” of mourning jewellery and, at the same time, the beginning of the decline of the noble mourning materials.

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