Joachim Wtewael's Mars and Venus Surprised by Vulcan is among the highlights of Christie's Old Master & British Paintings Evening Sale in London on July 3.

The previously forgotten copper panel, which the Dutch Mannerist produced in 1610, is expected to sell for £2m-4m.

Wtewael’s copper panel works are the artist’s most valuable

The work, discovered among the property of a French noble family during a Christie's valuation, is said by the auction house to embody "the full scope of Wtewael's accomplishment".

It last changed hands in the mid 19th century at a Christie's auction.

Wtewael's copper works are the artist's most valuable. His oil on copper Adam and Eve achieved a record $6.2m for the artist at Sotheby's in 2011, making more than five times its $1.2m high estimate. The upcoming auction should push that record close.

John Constable's The Lock will also feature at the sale, with an estimate of £20m-25m, while Rembrandt's A man in a gorget and cap is expected to make between £8m-12m.

Richard Knight, co-chairman of old master and British paintings at Christie's, commented: "Our sale this July brings together an extraordinarily rich mixture of old master and British paintings - perhaps the most significant in recent years and certainly the most valuable.

"The sale as a whole boasts exceptional works from all schools and periods, providing so many exciting opportunities for discerning collectors in today's very dynamic market."

The auction has a total high estimate of £88m.

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