The jewellery was stolen in May 2012 but details of the unsolved crime have just been disclosed by Leicester City Council following a Freedom of Information Act request.
Since the theft, the council has invested £90,000 in upgrading security at the museum.
Assistant mayor for culture Piara Singh Clair said he understood a catch on the display cabinet holding the Egyptian jewellery had been broken.
He said: "Our collections at New Walk are displayed across many rooms and galleries. Despite the best efforts of staff, this happened. You cannot keep your eye on every item or display. It is disappointing someone would want to steal items that were on display to be enjoyed by museum visitors."
Much of the council's collection was donated by the British School in Rome and the Egypt Exploration Society in the late 19th and early 20th centuries.
It has also been revealed two pieces of modern South Asian jewellery, worth £50, were stolen in April 2012.
Three rhino horns were reported stolen from a storage area at the museum in September 2012.
It is thought they were taken for the black market trade in some Asian countries, where they are consider to have medicinal properties.
Three items of 19th and 20th century costume jewellery, worth £50, were stolen from Leicester's Newark Houses museum in February 2012.
They were taken from the street scene exhibition.
The council said none of the items have been recovered but an insurance policy covered their loss, except for the on-loan rhino horns which have no formal insurable value because trade in them is illegal.
Police said investigations into the thefts were continuing but no arrests had been made, except in the case of the rhino horns, where a man was questioned but not charged.
Anyone with information on any of the thefts should call the Leicestershire police on 101.
Author: Dan Martin | Source: Leicester Mercury [January 16, 2014]