In 2012, a delicately modelled bracelet came to the attention of Christie’s auction house, an Art Deco bangle with a flower motif from the 1920s, resplendent with ruby palmettes and pear-shaped cabochon sapphires. It had been valued between £8,000 and £12,000, a fair sum for an unusual piece. However, on closer inspection, specialist David Warren, then senior international director of Christie’s Jewellery, spotted the unmistakable “Van”, from a Van Cleef & Arpels signature. With the help of the Parisian Maison, the bracelet was identified as belonging to one of its rare early collections, and it sold for £290,000. 

That’s the difference a name makes.

“A finely crafted, enamel art nouveau brooch can command a £20,000 price tag,” says Kristian Spofforth, Head of Department, Sotheby’s Jewellery, London. Find a Lalique signature on it, though, and “add a nought”.  

The same jewels, set in the same manner, yet, without the signature, the value can be significantly less. The signature is an indicator that it comes from one of the most celebrated houses, which has the means to employ the world’s top craftspeople.

“If it is one of the top makers, a signature can add 50, 100 or even 300 per cent to the value,” explains Keith Penton, head of Christie’s jewellery department. “Jewellery designed and produced by leading makers – for example Cartier, Fabergé, Harry Winston, JAR, Lalique, Van Cleef & Arpels – represents a very high standard.” However, don’t expect a signature magically to transform the value every time. “Cartier was such a prolific producer, for example, that a signature on traditionally-designed items will improve the value, but not necessarily dramatically,” he says, cautiously.

 The name above the door says: ‘The world’s top craftspeople’

Cartier, Van Cleef & Arpels and Harry Winston are still highly sought after, as well as contemporary pieces from designers such as Viren Bhagat, Wallace Chan and Edmond Chin, which Penton cites as the leading names fetching big sums at auction. Other makers enjoying a strong following include Belperron, Boucheron, Bulgari, Chaumet, Jean Schlumberger, Tiffany, David Webb, and Raymond Yard.

Just occasionally, prices at auction for signed pieces reach sky-high levels. A Belle Epoque devant-de-corsage brooch by Cartier in 2014 achieved CHF15.8 million and became the most expensive signed jewel ever auctioned. Signed Art Deco Tutti Frutti pieces by Cartier are particularly in demand, alongside jewellery by contemporary designer JAR. The Cartier love bracelet is a good place to start a collection, although an early version signed by its creator, Aldo Cipullo, is still a rare find. 

An early version of Cartier’s love bracelet signed by its creator Aldo Cipullo would be a rare find © Denver Post/Getty Images

It is wise to seek out the more under-the-radar houses, too. “It is also not uncommon to see pieces from lesser-known jewellery houses, designed by noted designers,” says Penton. Examples include Maurice Duvalet, a French jewellery designer who worked for American jewellers Charlton & Co., founded in New York in 1909. Duvalet often made trips to Paris, seeking the trends and inspiration of the city and interpreting these Art Deco designs for the American tastes during the 1920s. A decade later, the depression ended the marque’s success. Charlton & Co. branches and workshops were closed and Duvalet, who had propelled the firm to new heights, was let go. “He later went on to create masterpieces for Van Cleef & Arpels, such as the iconic ballerina brooches, but his early designs from his time at Charlton & Co. remain sought-after and often offer collectors exceptional value compared to one of his pieces which boast a Van Cleef & Arpels signature,” explains Penton.

Then there are the unsigned pieces, but with oodles of provenance, such as the ruby and diamond heart locket, circa 1850-60, formerly in the collection of Eugénie, The Last Empress of France, which came up for auction in 2019.

The Eugénie locket: an unsigned jewel of exceptional beauty and provenance, which likely originated from Chaumet

Her love of jewellery was legendary and the very best jewellery designers worked hard to remount and create new pieces to suit her personal taste, including Chaumet, and it is from this house that the locket likely originates. The locket was included in the 2008 exhibition, Le Musée Chaumet, “Le Grand Frisson - Bijoux de Sentiment, de la Renaissance à nos jours”, in Paris, however, the locket predates the period of Joseph Chaumet, who was director of the eponymous house from 1885-1928. “This unsigned jewel is of exceptional beauty and provenance and remains an important historical jewel,” says Penton. With an estimate of between £10,000 and £15,000, it actually sold for £41,250.

Penton adds that the Art Deco period generates most interest, followed by Belle Epoque, Retro Period, Art Nouveau and Arts & Crafts. And for those “under-the-radar “makers? Kutchinsky jewellery, which was big in the 1970s, is starting to come back, so keen collectors, says Spofforth, should keep an eye out for these flamboyant pieces.  

In the end, however, does it really matter who signed it – or not – if the piece of jewellery moves you? “If you like it and think it beautiful... and the designer goes belly up in six months’ time… then you still have a piece you love,” argues Spofforth, speaking about seeking out contemporary signed designs. 

Most jewellery was not signed – although usually hallmarked and sometimes with a maker’s mark – until the 20th century. “Over the last 10 years or so, there has been a huge emphasis on signed 20th-century jewels and this has overshadowed superb unsigned examples of the same period, and particularly 19th-century jewellery, which was largely unsigned,” explains jewellery historian Vivienne Becker. “I believe it’s important to use your own judgement, of design, quality, craftsmanship, and not rely solely on a signature.

“The concept of a signed jewel, part of the cult of individuality, is a relatively modern concept. And not everything made by a great Maison was superlative.”

Becker says she likes to look for Victorian jewellery, which she considers “undervalued”. She also points to the possibilities of 1980s work, such as Bulgari’s Monete coin-set jewellery, noting that jewels from this time are a growing trend, now that we have enough distance from the decade to look at it objectively, and for the style to look and feel right. 

But remember, “signature alone isn’t enough”. Becker advocates searching for the strongest style of any period, and for the best possible materials and craftsmanship. Then you cannot go wrong.