In 1956, the director of Canterbury Museum, Roger Duff, travelled to China. One purpose was to meet with Rewi Alley, the New Zealander already famous for his work with the Chinese Communists and a deft collector of Chinese antiquities. 

Duff and Alley had been corresponding since the 1940s and Alley was keen to donate some of his collection to the museum in his native Canterbury.

Alley's "pleasure was to collect until his hotel room overflowed, when he would unload on to friends," wrote Duff in his diary. "My arrival coincided with the need to unload – after which Rewi will doubtless start again."

But there was a barrier to the gift. In 1950, shortly after the Communists seized power, they banned exports of Chinese art and antiques. Foreigners had been pilfering Chinese history for a long time and the Chinese authorities wanted the remaining objects for their own museums.

The items, listed by renowned auction house Sotheby's, include moa leg bones, a golden huia beak brooch, a kiwi skeleton, a taxidermied bird, and a patu and mere - two types of Māori clubs.

Mike Dickison, former curator of Whanganui Regional Museum, said it was not unusual for items like these to be sold overseas, but it was sad the sellers did not seem to know the context of most of the artefacts. For example, the Huia beak brooch was from Whanganui, he said.

"A founder of our museum, Samuel Drew, was a jeweller and natural history expert and taxidermist - probably the only person in Whanganui who'd be taking natural history objects and making jewellery out of them.

"So if they'd bothered to do any research, they probably could have found some context and perhaps even returned it to the area."

One of the few items listed with some background information was a greenstone mere, or short club. The description said it was given by Ngāti Whātua chief Pāora Tuhaere to Admiral Tryon in 1885, after a boat race. The chief's only request was that the taonga be kept in the admiral's family.

"Pāora then handed over the ancestral mere to Admiral Tryon, who in suitable terms acknowledged the compliment, and said that he would value the gift as coming from a chief who had always been conspicuous for his loyalty," the description read.