A gold and diamond broach presented to the wife of the Captain of HMS Coventry when launching the ship at Birkenhead in June 1974 is going under the hammer.

The broach, which will be sold by Bonhams on September 25 in Knightsbridge, is one of the last surviving links to the ill-fated HMS Coventry which was subsequently sunk in the Falklands conflict after coming under heavy enemy aircraft attack.

John Millenstead, head of Bonhams coins and medals department, said: "This broach is one of the few remaining links with the HMS Coventry which because of her gallant service in the Falklands makes this small item of great emotional and historic value."

The gold and diamond brooch is of abstract design with 18 carat yellow gold textured bark finish accented by brilliant-cut diamonds.

The broach features diamonds of approximately 0.75 carat in total.

It is hallmarked Birmingham 1972, and bears the maker's mark D&F for Deakin and Frances, height 2.8cm.

The broach is expected to fetch between £800 and £1,200.

The lot comes with a wooden shield for HMS Coventry, with a plaque attached to the reverse which has the inscription - "Presented to Lady Lewin by the Senior Officer and Ships Company of HMS COVENTRY on the occasion of the Ships launch 21st June 1974".

HMS Coventry was a Type 42 (Sheffield Class) Destroyer laid down by Cammell Laird and Company, Limited, at Birkenhead on 29 January 1973.

She was launched on 21 June 1974 and commissioned on 20 October 1978.