London - A stunning Fabergé Imperial Egg bought at auction in New York in 1964 is being hunted down by a London jewellers.
The gem-encrusted gold/sapphire/ruby/diamond trinket, which looks like a flower-festooned Easter egg in precious metal basket, opens up to reveal a beautiful gold Vacheron & Constantin Swiss watch, one of several commissioned for the House of Fabergé.
It last changed hands for $2,450 at Parke Bernet's March '64 sale following identification as an Easter 1887 gift from Tsar Alexander III to his wife Tsarina Maria Feodorovna.
Since the sale it has gone off the auction industry radar prompting ludicrous theories about the identity - and antique savviness - of its alleged owner.
This weekend a spokesperson for a renowned London-based jewellers - speciality: fawning over oligarchs! - said that the bijou ornament may be in Britain.
And that the lucky owner 'will have no idea' of its provenance, significance or financial value!'
At their Carnegie Hill condominium this weekend a mystery US Big Oil couple laughed themselves silly at the very idea of such monumental ignorance.
"Sounds like a phishing expedition to me!" Dr Lamar Madison chuckled over breakfast as the Fabergé egg story hit the syndication agencies.
"Just because it's vanished off the industry radar doesn't mean it's gonna turn up on some tacky Antiques Roadshow, heheh!"
The artefact has quietly accumulated the staggering - albeit estimated - £20 million value in the company of some 100 other precious Fabergé 'siblings' that form part of the Madisons' Russian portfolio.
BBC TV presenter Fiona Bruce is 47.