The owner of a specialist coin and jewellery shop was forced to the floor as two men emptied out the firm's safe in a robbery in Bedfordshire.
Police said a well-dressed man entered Cambridge Coins and Jewellery in the High Street, Biggleswade, at about 1100 GMT on Wednesday.
The robber asked to see a valuable sovereign. The owner was then pushed to the ground before a second man entered.
They made off on foot with a large sum of coins, cash and jewellery.
The main offender is described as a white man, aged in his 60s and 6ft (1.83m) tall.
'Frightening experience'
He wore a brown trilby-style hat, brown suit jacket, black trousers and leather gloves. The second man was in his 30s and wore a blue hooded jacket.
Det Sgt Graham McMillan, investigating, said he wanted to speak to anyone who saw the well-dressed man hanging around the store before the robbery or recalled seeing anything suspicious in the High Street area, such as an unfamiliar vehicle.
Det Sgt McMillan said: "Although no-one was hurt, this was an extremely frightening experience for the owner, who did exactly the right thing by complying with the offenders.
"I am keen to speak to an elderly lady who approached the shop and was refused entry by the offender.
"The lady was wearing a red cardigan or jacket and pushing a shopping trolley. She may not have realised what was happening at the time."
He added: "It is very likely the offenders will now try to sell this property on and we would urge any dealers or anyone in the trade to contact us if they are offered property they believe is stolen."
Anyone with information is asked to contact Bedfordshire Police.
