An archive of photographs taken in China by John David Zumbrun and Camera Craft, Beijing is valued at $300,000-500,000 ahead of a sale of artefacts from the 20th century.
The sale is due to take place in Bonhams Los Angeles on June 5.
The lot comprises almost 2,000 images (ranging from postcards to negatives) taken between 1910 and 1929 that include panoramas of Beijing and pictures of ordinary people going about their lives during the transitional period between the feudal system and military rule.
Zumbrun managed to achieve near exclusive access to areas usually off limits to Westerners - including the imperial court and the last emperor Puyi.
Last year a single panorama of Beijing by the photographer made an impressive $27,500 at Bonhams Los Angeles.
A rare graphic archive pertaining to Yakov Cernikhov is estimated at $350,000-450,000.
Chernikov is considered one of the most innovative architects of his era and worked predominantly within the constructivist style, creating some of the most striking Soviet buildings.
The archive consists of around 122 drawings and 953 pencil sketches that show a variety of architectural structures, many of which were published in journals throughout the 1920s and 1930s.
Also included in the sale are an original set of Apple logos that used to hang outside the company's offices in Cupertinino, California.
We have a range of artefacts available that tell the story of the 20th century. Check out our memorabilia section here.
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