Gold diamond rings, bracelets and necklaces are among the items of valuable jewellery taken from a home in Preston.
An elderly homeowner was away for four nights and came home to Whittingham Lane, Broughton, to find around £20,000 worth of jewellery had been stolen.
Pictures of the items have been released by Preston Police who say some costume jewellery is also in the haul.
The theft happened sometime between Wednesday 31 May and Sunday 4 June.
PCSO David Reid said: “We believe that the house was targeted whilst the woman was away and the offenders have gone in for the jewellery in particular as no other items were taken. To think that someone would deliberately do this to an elderly woman is utterly despicable.
“These pieces of jewellery are highly sentimental to the owner and so we would love to be able to reunite her with her things which she has collected over many years.
“Please take a look at what was taken and if you have seen it, perhaps you have been offered it for sale, please come forward and speak to us.”
Anyone with information call police on 01772 863390 quoting incident reference 1438 of 4th June.
Alternatively independent charity Crimestoppers can be contacted anonymously on 0800 555111 or online at crimestoppers-uk.org.