This work has only come up for auction twice in the past 20 years and boasts a signed letter from Cunningham’s son averring that it is “one of the earliest” prints by the artist. According to Darius Himes, the international head of photographs at Christie’s, Cunningham was “a key figure of the period between the wars” but made waves even earlier in her career, not least because she was a woman working in a field dominated by men, but also because she made photographic nude studies as early as 1910. Though she often captured male subjects in provocative poses, her images of the female body—frequently her own—accentuated by nothing but light proved controversial. Imogen Cunningham, Two Sisters (1928). An American Journey: The Diann G. and Thomas A. Mann Collection of Photographic Masterworks at Christie’s, New York, 4-5 October. Estimate $80,000-$120,000. Photo: Courtesy of Christie's

This aluminium sculpture by the Sudanese artist Ibrahim El-Salahi is modelled after the Haraz tree, an acacia native to Sudan that appears frequently in the artist’s work. In the catalogue of his solo exhibition at the Tate Modern in 2013, the artist writes that the Haraz tree “through all, remains steadfast, silently watching over the passage of seasons and time”. During the fair, the artist will also present his first public work of art, a piece that expands on the theme of the Haraz tree. Last year, a portrait of a Sudanese man made the artist’s auction record, fetching €87,500 (€15,000-€20,000) at Ader auction house. Ibrahim El-Salahi, Meditation Tree (2018). Vigo Gallery at 1-54 Contemporary African Art Fair, London, 4-7 October. £55,000. Photo: Will Amlot; courtesy of the artist and Vigo Gallery.

This oil painting by the German artist Gerhard Richter is one of more than 150 works from the estate of the TV and film rights negotiator and art collector Howard Karshan that Phillips will offer across a series of sales in London and New York. Cheyenne Westphal, the Phillips chairman, says Karshan had “a keen eye for acquiring works on paper, the majority of which capture the intimacy and unique sensibility of drawing” and she describes this work as “a striking early piece" from Richter’s photorealist paintings of the 1960s. In his lifetime, Karshan bought several works by Richter, among them a later abstract oil painting called Busch (1985) (est £800,000-£1.2m) also offered in this sale. Gerhard Richter, Hände (1963). 20th Century and Contemporary Art Evening Sale at Phillips, London, 5 October. Estimate £2m-£3m.

This Chinese porcelain vase—made by Tang Ying, the famous superintendent of the Jingdezhen kilns—is the pair to that sold for a record £43m at the small auction house Bainbridges on the outskirts of London in 2010. Except that vase was never paid for—it was eventually sold privately for half that amount through Bonhams. Hence the cautious estimate here, although Sotheby’s Nicolas Chow says this is “a strategy… in order to generate the most competition.” He expects it “to fetch multiples of the estimate”. Named after the firm of Yamanaka & Co, which sourced objects in China for galleries in the West, the vase was bought by a Japanese collector in 1924 and has not been for sale since. The Yamanaka Reticulated Vase, Qianlong period (1736-95). Chinese Works of Art at Sotheby’s, Hong Kong, 3 October. Estimate HK$50m-$70m (US$6.4m-$9m).

Considered the father of Nigerian Modernism, Enwonwu is well known for his monumental portraiture. Depicting a masked male figure, Ogolo was painted shortly after the death of the artist’s brother, the funeral services for whom included a traditional masquerade ritual. The work is similar to the Spirit of Ogolo, which sold at Bonhams in 2016 for £218,500. That was, however, before Tutu (one of the artist’s most significant portraits) appeared at the auction house in February. Though Tutu was estimated to fetch a price within the same range, it went for £1.2m to an unknown bidder, shattering the auction record for a work by any Nigerian Modernist and doubtless driving hopes upward for Ogolo. Benedict Chukwukadibia Enwonwu, Ogolo (1989). Africa Now at Bonhams, London, 4 October. Estimate £200,000-£300,000. Photo: Courtesy of Bonham's.

House plants play a prominent role in Lucian Freud’s paintings, their leaves and stems often used to abstract effect in his compositions. The heart-shaped leaves of the zimmerlinde (or house lime) make repeat performances—in 1948, he depicted his first wife, Kitty Garman, peering out from behind a zimmerlinde branch in the Girl with Leaves. The following year, while still married to Garman, he met Lady Caroline Blackwood to whom this oil on canvas is dedicated: “For Caroline with all my love Lucian” is written on raw canvas at the lower left. Originally in Blackwood’s collection, it was bought by the grandmother of the current owner in the 1950s. Lucian Freud, Still Life with Zimmerlinde (around 1950), Post-War and Contemporary Art Evening Sale at Christie’s, London, 4 October. Estimate £400,000-£600,000.

The Sitzmaschine—literally, a machine for sitting—was designed by the Wiener Werkstätte co-founder Josef Hoffmann in 1905 for the Purkersdorf Sanatorium in Vienna, and has since become an emblem of Vienna Secession design. The reclining chair was designed to be easy to produce and, says the dealer Alexandre Guillemain, “it is the first object to claim a functionalist approach. Its geometric forms and the simplicity of its conception presage the founding principles of the Modern movement”. This example is from the first edition—other chairs from the edition are in the collections of the V&A Museum, the Musée d’Orsay and Moma, among others. Josef Hoffmann, Sitzmaschine armchair, produced by J&J Kohn (around 1907). Alexandre Guillemain at PAD London, 1-7 October. Around €26,000. Photo: Courtesy of Alexandre Guillemain.

Art market

Object lessons: from a Qianlong-era Chinese vase to a painting by the master of Nigerian Modernism

Our pick from this week's fairs and auctions

Benedict Chukwukadibia Enwonwu, Ogolo (1989). Courtesy of Bonhams.

Benedict Chukwukadibia Enwonwu, Ogolo (1989). Courtesy of Bonhams.