A goose in China has laid these incredible eggs with black yolks.

The incident took place at a farm near the city of Hangzhou in the Chinese province of Zhejiang last week.

The goose owner, name not disclosed, posted a clip of him cracking open two eggs with black yolks in a dish on the Chinese social network Douyin, adding that a mulberry tree is located near to where his geese are kept.

The owner suspects that the goose in question ate a load of mulberries from the tree, claiming that this resulted in the black yolks, however, experts are reportedly sceptical and interested in finding out the reason and want to carry out tests of their own.

According to the news site Baidu, officials from the Academy of Agricultural Sciences have contacted the family about conducting analysis on the eggs.

There have been no further reports on the cause of the unusually coloured eggs.