The week in art

Bargain bin find of the week goes to one Philip Mould. The art dealer paid £120 on eBay for a portrait he suspected was a genuine work by Thomas Gainsborough. A little acetone and a session of paint-stripping later, what emerged was indeed an early portrait by the 18th-century artist, which someone else had inexplicably painted over Photograph: Courtesy of Philip Mould/PR

Christie's is experiencing a 78% decline in contemporary art sales as the shaky economic climate forces sellers to hold back. Despite this, works by modern masters such as Jeff Koons and Peter Doig continue to sell well. This 9ft cityscape by Doig, titled Night Playground, sold for a hefty £3m – double its estimated price Photograph: Katie Collins/PA

Restoration of Michelangelo frescoes in the Vatican has uncovered what experts believe to be a self-portrait by the artist. Chief restorer Maurizio De Luca says that in the Pauline Chapel's The Crucifixion of St Peter, the horseman with the blue turban is clearly Michelangelo. 'This is an extraordinary and moving discovery,' he said Photograph: The Bridgeman Art Library

Sculptor Andy Scott unveiled his design this week for a new public artwork, a 10-metre-high steel woman. The work, which will cost £250,000, is to be installed in Cumbernauld, North Lanarkshire, recipient of a 2001 Carbuncle award for being 'the most dismal town in Scotland' Photograph: www.idealimages.co.uk

Tate Liverpool has announced its autumn lineup this week, which begins with a retrospective of the radical and subversive French artist Jean Tinguely. The show, Joyous Machines, is co-curated by British artist Michael Landy and will offer a study of Tinguely's rarely examined early career. It will run from 2 October 2009 until 10 January 2010 Photograph: Urs Flueeler/Keystone/Corbis

Damien Hirst seems to be playing hard to get with the Royal Academy in London, which has offered him the chance to become a Royal Academician, one of elite few who govern the 241-year-old arts institution. The artist, who once dubbed the RA 'a big, fat, stuffy old pompous institution', despite having exhibited there himself, has not yet made his decision Photograph: Shaun Curry/AFP/Getty Images

Art gallery Haunch of Venison, owned by Christie's auction house, has announced the closure of its Zurich art space, claiming a desire to focus resources on exhibition programmes in other cities. The London art specialists already have outposts in Berlin and New York and are said to be headed for expansion in China Photograph: PR