Thugs used a crowbar to smash their way through the shutters of The Gold Bar in Green Lanes, Haringey on Saturday 29 January.
After jimmying open a security cage the thieves escaped with nearly £50,000 worth of diamonds, earrings and pendants.
Mustafa Salih, 64, who has run the small jewellers for 33 years, said it was the first time a robber had been successful after dodging gunmen over the years by simply hiding in the back.
Speaking to the Standard Salih said: “I feel terrible, like just running away from here. If I was in at the time there would have been a bloodbath.
“I have worked for this my whole life and if I just hand it over I may as well be dead.
“I tried to get insured back when the Broadwater Farm riots were going on but it has been sky high since then.”
He claims his barber had tipped him off to a couple of white guys scouting the business sitting in a van the day before the raid.
He added: “What can the police do? These guys knew what they were doing. They will be doing it again for sure.
“The haul won’t be enough for them if there’s two or three they would have probably spent it all on drugs by now.”
A Scotland Yard spokesman said: “At around 1.50am on Saturday, 29 January, police were called to a burglary at a shop on Green Lanes, Haringey.
“Officers attended and found that the front door had been forced and entry gained.
“A search was carried out with the assistance of the Met’s dog unit.
“The owner reported that a quantity of jewellery had been stolen from the shop.
“Enquiries, including examination of CCTV and forensic analysis, is ongoing.
“No arrests have been made.”
Anyone with information should call 101 with reference 718/29JAN.