"When we were forced to leave Russia in 1974," said Vishnevskaya in the Sotheby's statement, "we had to abandon everything; all of our property was left behind in Russia. We left, quite literally, without a penny to our name ... When we left — Rostropovich with a cello and Kuzya, a Newfoundland dog, and I with two suitcases and two children — we had to build our lives all over again from nothing and when in 1978 we were stripped of Russian citizenship, we bought the flat which we've lived in for all these years."

Rostropovich and Vishnevskaya had decided to sell that Paris apartment — "which we decided to turn into a Russian house," as she put it — auction the belongings and relocate permanently to the Moscow area before the maestro's death earlier this year.

And the couple was serious about turning their Paris dwelling into a Russian home in exile. "They recreated Czarist Russia," said Jo Vickery, head of Sotheby's Russian department in London, to The New York Times. "They were big buyers way before Russian art and objects became so popular. In the 1980s and '90s they helped drive the market."

"It's the best collection of Russian art ever put together outside Russia," Russian art consultant Ivan Samarine told Bloomberg News. "Vishnevskaya and Rostropovich gathered this art using their talent and instinct together with expert advice."

"We used to buy things from countries all over the world," said Vishnevskaya in the statement. "I love porcelain. Russian porcelain is somehow special. I can instantly distinguish it from other types — if there are several beautiful objects displayed together I immediately pick out a Russian work, I can see it as though I've been familiar with it since childhood."

The collection includes plenty of porcelain, much of it from the Imperial Porcelain Manufactory, as well as Russian glassware, enamelware and ivory from the 18th, 19th and early 20th centuries. But the most newsworthy, and most valuable, items in the collection are the paintings. Among the notable examples are Sergei Ivanov's Boyar's Serfs (mid-late 19th century), estimated at £40,000-£60,000; Ivan Bilibin's The Hunt (late 19th-early 20th century), estimated at £120,000-£180,000, and Nicholas Roerich's icon-like Treasure of the Angels (1905), which Rostropovich and Vishnevskaya purchased at Sotheby's for £287,500 in 1998 and is now estimated to be worth £800,000-£1,200,000.