Battle royale in the aristocracy as art collector sues Lord Great Chamberlain over £1.75m 'Louis XV' urns

One of Britain's most famous aristocratic families is being sued by the daughter of a former owner of The Times over an alleged misrepresentation of the provenance of two bronze urns worth £1.75m.

The acrimonious dispute between the 7th Marquess of Cholmondeley and Taylor Lynne Thomson, daughter of the Canadian press baron Lord Thomson of Fleet, has scandalised the art world. And yesterday a judge cleared the way for the allegations to be publicly aired in the High Court in London next year.

Ms Thomson, a well-known art collector, claims that the two gilded vases she bought are not antiques from the period of Louis XV but instead were made early in the 19th century.

She is suing both Lord Cholmondeley, 42, the Lord Great Chamberlain, the Queen's representative in the House of Lords, and Christie's which arranged the auction of the vases. Lord Cholmondeley, director of the 1999 movie Other Voices, Other Rooms and whose fortune is said to be worth more than £100m, sold the gilt and marble vases eight years ago to Ms Thomson when she outbid Ann Getty, a relation of the billionaire Getty family.

In the auction catalogue the urns were described as "a pair of Louis XV porphyry and gilt-bronze two-handled vases designed by Ennemond- Alexandre Petitot".

But now Ms Thomson, a collector of "museum-quality" art works, is alleging they were nothing of the kind. She claims she is a victim of misrepresentation and is demanding damages or her money back. Lord Cholmondeley and Christie's are both vigorously defending the claim. Christie's lawyers insist the urns were made in the 18th century, during or shortly after the reign of Louis XV, and that they were "accurately and properly described" in the catalogue. The case is expected to cost more than £500,000 in legal fees, last 15 days and hear evidence from some of the leading art experts in the country. Yesterday Mr Justice Jack, the High Court judge who set down the case for trial in March next year, acknowledged that the legal costs represented "quite a big chunk" of the £1.75m at stake. But he said the case would hopefully resolve "a crucial issue for the art world" never before considered by the courts. The vases were sold by Lord Cholmondeley in 1994 along with another £19m worth of treasures from Houghton Hall, his family's 18th-century Palladian mansion in Norfolk. Buyers from around the world travelled to the auction, billed as "the greatest sale of art treasures for a decade".

When the 6th Lord Cholmondeley died in 1990, his will indicated a fortune of more than £100m including his estates and art collection. The artefacts were sold to help pay for the maintenance of the family's estates. Among other lots were a painting by Jean-Francois de Troy, La Lecture de Moliere, which sold for £4m, and a double-sided sketch by Rubens, which sold for £1.7m.

Christie's lawyers also point to the "outstanding quality and beauty" of the urns and say the catalogue description was an "expression of opinion", rather than fact, and was based on an "exercise of judgement" by Christie's experts.

There were no doubts about the vases raised before the sale and the catalogue made clear the "absence of any pre-1921 provenance".

Christie's also point to its "terms of business", which place limits on the auction house's potential liabilities, but Ms Thomson argues that those terms fall foul of the Unfair Contract Terms Act.

Lord Cholmondeley also denies Ms Thomson's breach of contract claims, saying the catalogue description was Christie's responsibility. Andrew Onslow, for Christie's, told the judge that one metallurgical expert had, since the sale, expressed the view that the urns were "of late 19th-century manufacture".

But, he added, the expert's report had "come in for very considerable criticism". He accepted there was a fashion in the 19th century "for 18th century revivals", but said it was nevertheless Christie's case that the catalogue description was accurate.