Three men threatened staff with knives and swords and smashed open display cases at the Hamilton & Inches store in George Street, Edinburgh, at around 11.40am last Friday.
They made their escape in a white BMW car driven by a fourth man, which was later found abandoned in Gloucester Lane. Detectives believe the suspects then got into a dark-coloured car and fled the area.
Eight Patek Phillipe watches ranging in value from £22,000 to £66,000 were among the items stolen. An inventory of the losses is still being produced.
Police said officers would carry out high-visibility patrols in George Street, Frederick Street, North Castle Street and Gloucester Lane today to gather information from anyone who was in the area at the time last week and might have seen anything suspicious.
Detective Inspector Carol Craig said: "So far, the response and assistance from the public has been fantastic and we continue to progress a number of lines of inquiry.
"However, we have yet to receive that vital piece of information that will lead to tracing those responsible for this robbery and recovering the stolen jewellery.
"Police will have a large presence in a number of streets linked to the investigation and we would urge any members of the public who were in these areas last Friday during the times around the incident to speak with officers if they have information that can assist with our inquiries.
"Alternatively, you can make an anonymous report via the charity Crimestoppers on 0800 555 111."
The three robbers who entered the shop were dressed in dark clothing.
Robert Kirk Inches and his uncle James Hamilton opened their first premises at 90A Princes Street under the name Hamilton & Inches on November 10, 1866.