French Jet
French jet is a misnomer - not jet at all, but deep black pressed glass which, from the 1860s onwards, conquered the Victorian widow's-mourning-jewellery segment as inexpensive mass-produced ware.
Written by Dr. Helene Vasall
French jet is one of the few mourning materials of the 19th century that does not deliver what its name promises - and it is precisely for that reason important to the social history of Victorian mourning jewellery. While Whitby Jet clothed the court aristocracy and the upper middle class, and Berlin iron served Prussian self-image, French jet was the first industrially produced mourning jewellery for the broad middle class.
What it really is
French jet is pressed glass coloured black throughout. Manufacture follows the usual pressed-glass process of the mid-19th century: black glass is produced in the melting furnace (coloured with manganese, cobalt and iron oxides), pressed into metal moulds and slowly cooled in the annealing oven. Once set, the pieces are deburred with a steel wire and mounted on card or brass backings.
The jewellery form is usually a brooch or a pendant with a front image in relief - weeping willow over urn, anchor, oak leaves. The reverse is flat, often fitted with a plain brass pin or loop. Complex pieces (multi-part necklaces, bracelets with articulated links) were assembled from individually pressed elements.
Market breakthrough from the 1860s
Until the end of the 1850s, Whitby Jet was the undisputed standard for Victorian mourning jewellery. As formal court mourning spread through the middle classes, demand rose drastically and Whitby production could not keep pace. French jet positioned itself in that gap - first through Parisian wholesalers, then through London's West End.
Three factors made its success possible:
- Price. Around 1870, a French jet brooch cost a third to a fifth of a comparable Whitby brooch.
- Availability. The Parisian glassworks produced in quantities that the hand-craft capacity of Whitby could never have reached.
- Optical deception. At two metres' distance, French jet is visually indistinguishable from Whitby jet. For the social function of mourning jewellery - to signal visibly that one is in mourning - that was enough.
In the 1880s, Bohemian glassworks (above all Gablonz, today Jablonec nad Nisou) produced French-jet-type pieces alongside the French ones. These are often technically finer and are today likewise traded on the collectors' market as French jet.
The Whitby industry under pressure
The Whitby manufactories saw French jet as a threat from the outset. In petitions to the British Board of Trade they demanded a protected-designation regulation such as existed for Sheffield Plate - in vain. The Whitby industry responded on two fronts: on the one hand with advertising campaigns that set the "genuine" jet apart from the glass imitation, on the other by opening up the lower market segment with simple jet semi-finished goods.
Nevertheless, the Whitby market contracted markedly after 1890. As formal court mourning lost significance around 1900, French jet disappeared as well - unlike Whitby Jet, however, its disappearance left no gap; the manufactories simply switched to other pressed-glass products.
Identification today
Anyone wishing to classify a piece of black Victorian jewellery checks in this order:
- Weight in the hand. French jet is markedly heavier than Whitby jet.
- Temperature. Jet warms up as it is worn, glass does not.
- Fracture edge. With glass, small damages show a conchoidal, glossy break.
- UV light. Jet fluoresces faintly yellowish, glass stays dull.
- Reverse-side mounting. French jet almost always sits on brass or iron plates; jet is usually set as solid material or drilled through directly.
Repairs to French jet are practically never worthwhile. A crack in the glass renders the piece visually worthless; the collectors' segment accepts no glued pieces. Anyone who inherits an intact piece should keep it in a soft case - the material is hard, but brittle.
French jet today
In today's jewellery trade the term French Jet is a historical one - new pieces are practically never produced under this name. Anyone wishing to work with deep black in modern memorial jewellery uses either onyx, black-enamelled gold or black ceramicised materials. The 19th-century misnomer is history - but as evidence of how early mass-produced ware broke into the mourning jewellery market, French jet remains instructive.
Questions about this entry
- How does one distinguish French jet from genuine jet?
Weight and temperature: being glass, French jet is markedly heavier and always cool in the hand, whereas jet is strikingly light and warms to body temperature within seconds. Visually, edges and breaks help - glass shows a conchoidal fracture, jet a dull one. Under UV light jet fluoresces faintly yellowish, while glass stays dull.
- Why was French jet so successful?
Whitby jet was caught in a high-Victorian supply bottleneck: extraction was limited, prices rose, and the middle classes could not afford original pieces. French jet was three to five times cheaper, virtually indistinguishable to the eye and available across Europe through Parisian and London wholesalers. It was the first mourning jewellery of the middle class.
- Does French jet have any collector's value?
Yes, although markedly below that of jet. Well-preserved brooches and necklaces from the peak period (1870–1890) are sought after, especially with an identifiable manufactory mark (Parisian workshops occasionally signed their work). Damaged material is practically worthless - glass cannot be restored.
Further reading
- Mourning Dress: A Costume and Social History - Lou Taylor (2009)
- Whitby Jet vs. French Jet - Identifikation - Helen Muller (2009)
- Pressglas-Korrespondenz - Archiv
Related entries
- Core conceptsWidow's Jewellery
Widow's jewellery is the graduated mourning jewellery worn by widows in the 19th century according to a strictly codified plan of court mourning - from deep matte black to half-mourning lilac, each phase with its own materials and its own formal language.
- Core conceptsMourning Jewellery
Mourning jewellery is body adornment that signals a death, binds the memory of a deceased person, or does both at once - since the 17th century a jewellery type in its own right, with a material language of its own.
- MaterialsJet (Gagate)
Jet - German *Gagat* - is a fossil, deep-black material formed from petrified wood which in the nineteenth century became the very epitome of Victorian mourning jewellery.
- MaterialsVulcanite (Ebonite)
Vulcanite is hardened, black-dyed natural rubber - an industrial invention of the 1840s which found wide use in Victorian mourning jewellery as an inexpensive alternative to jet.
- MaterialsWhitby Jet
Whitby jet is jet from the North English coastal town of Whitby - by far the most important deposit worldwide in the 19th century and the gold standard of Victorian mourning jewellery.
- PeriodsThe Victorian Era (1837–1901)
The Victorian era is the heyday of mourning jewellery - a period of more than sixty years in which court mourning codes, industrial mass production, new materials (jet, vulcanite, Berlin iron) and Queen Victoria's personal widowhood combined to produce a system of public and private mourning visibility without precedent in European history.
- Jewellery formsMourning Brooch
The mourning brooch is the central women's jewellery form of Victorian mourning wear - a brooch, often the size of a palm, pinned to dress, collar or veil, and today an almost exclusively historical field of collecting.