# Major Impressionist art auctions by Sotheby’s

> Live situation record from CLSTR: https://clstr.news/situations/major-impressionist-art-auctions-by-sothebys
> Updated: 2026-09-30T09:51:49.000Z. Sources: 42. Developments: 2.

Sotheby’s has announced two major upcoming auctions featuring significant Impressionist and Modern masterpieces from private collections that have been unseen by the public for decades.

In Paris, an auction scheduled for October 22 will feature 28 works from the Jeanne Schlumberger collection. The centerpiece is Claude Monet’s ‘Iris’, which is estimated to sell for between 22 and 30 million euros. This work has never been publicly exhibited and was previously known only through black-and-white photography. The collection, valued at over 40 million euros, also includes works by Paul Cézanne and Pierre Bonnard.

Following this, a New York auction is scheduled for November 18 to sell the Blaquier-Arrieta collection, with an estimated total value of approximately $450 million. Amassed by Argentine heiress Nelly Arrieta de Blaquier and her husband, the collection includes works by Vincent van Gogh and Paul Cézanne that have not been in public view for fifty years. Sotheby’s experts have characterized the collection as a “mini Musée d’Orsay” due to its high caliber.

The Blaquier-Arrieta sale will feature 12 masterpieces, including Vincent van Gogh’s ‘Châtaigniers en fleurs’, estimated at $180 million, and Paul Cézanne’s ‘Arlequin’, estimated at $120 million. Both pieces have not been publicly displayed for roughly half a century. The collection also contains works by Claude Monet, Pierre-Auguste Renoir, Camille Pissarro, and Edgar Degas. Prior to the New York auction, the artworks will undergo an international tour with previews in London, Taipei, Hong Kong, and Paris.

## Claims

- Sotheby’s will auction a collection of 12 Impressionist and Post-Impressionist artworks in New York on November 18. (corroborated by 3 sources)
- The total value of the 12 artworks is expected to exceed $450 million. (corroborated by 3 sources)
- Vincent van Gogh’s ‘Châtaigniers en fleurs’ is estimated to sell for $180 million. (corroborated by 3 sources)
- Paul Cézanne’s ‘Arlequin’ has an estimated value between $120 million and $150 million. (corroborated by 3 sources)
- The artworks were part of a private collection owned by the late Argentinian collectors Nelly Arrieta de Blaquier and Carlos Pedro Blaquier. (corroborated by 3 sources)
- The paintings have not been seen in public for approximately 50 years. (corroborated by 3 sources)
- The collection includes works by Monet, Renoir, Degas, Pissarro, Gauguin, and others. (corroborated by 3 sources)

## Timeline

### 2026-09-30: Blaquier-Arrieta Collection to be auctioned by Sotheby’s for $450 million

Sotheby’s will auction 12 rare Impressionist masterpieces from the Blaquier-Arrieta collection in New York on November 18, with total estimates reaching $450 million.

31 sources. https://clstr.news/cluster/sothebys-to-auction-450m-impressionist-collection-in-new-york

### 2026-09-17: Monet’s ‘Iris’ to be auctioned in Paris for up to 30 million euros

Sotheby’s will auction the Schlumberger collection in Paris on October 22, headlined by Claude Monet’s ‘Iris’, a previously unexhibited painting estimated at up to 30 million euros.

12 sources. https://clstr.news/cluster/claude-monet-paintings-to-be-auctioned-in-paris

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Cite as: Major Impressionist art auctions by Sotheby’s. CLSTR, https://clstr.news/situations/major-impressionist-art-auctions-by-sothebys