This is the mummy and its coffin which in 1825 the mummy was subject of the first ancient Egyptian mummy autopsy by Dr. Augustus Granville. The lady Irtyersenu lived somewhere around 600bce and the mummy is reported to have been found at Thebes.
The autopsy was presented before The Royal Society of London which caused a sensation at the time. Dr Granville found during the autopsy an ovarian tumor on Irtyersenu and surmised that she had died from it. Recent study has brought up that Irtyersenu also had Tuberculosis which is what more than likely what killed her.
The coffin and remains of Irtyersenu are kept in the British Museum though I have been unable to find them on the museums site.