"Police would like to acknowledge witnesses at the scene of the aggravated robbery who have assisted our inquiries."
The investigation remained ongoing and police could not rule out further arrests being made.
The lunchtime heist came just hours before a second store was targeted in Grey Lynn yesterday.
Four people entered Diamonds on Richmond with weapons just after 4.45pm, using them to smash the glass counters to retrieve the jewellery.
The thieves left in a car which was later located abandoned on Farrar St.
Stolen items were found inside the vehicle.
Police said inquiries into that incident are still ongoing.
On Monday, jewellery wholesaler TJ Handcrafted was another target in a daylight smash-and-grab.
Two men similarly used a hammer to break the glass counters of the store before fleeing in a car.
In a second incident across town the same day, shoppers were also left terrified after up to a dozen people attempted to break into the Michael Hill store at LynnMall in New Lynn.
Eyewitnesses told the Herald the perpetrators were armed with large hammers, crowbars and sticks.
They fled the scene after realising they could not break into the store.
Last week, shoppers were left shocked when robbers shattered glass cabinets at Michael Hill in the Newmarket Westfield mall.
And last month a Michael Hill store on the corner of Hurstmere and Lake Rds in Takapuna was the target of a daytime robbery.
Police later arrested a 20-year-old man and charged him with receiving stolen property.
