They then entered the building through an unsecured ranchslider door before Anderson armed himself with a screw driver and a pair of scissors. His alleged associate was armed with a .22 calibre rifle.
Two staff members were threatened and led to a toilet area where they were ordered to face the wall and their hands were bound with an electrical cord.
Shortly after, three other employees entered the office and were also taken to the toilet and bound.
Anderson's alleged accomplice demanded the shift manager lead him to the safe. Once it was opened, all the cash and jewellery were placed into a bag.
Cash and cheques worth $27,612 were stolen. The total retail value of the jewellery was $242,805 and consisted of about 300 items.
The shift manager's arms and hands were bound with sticky tape and she was taken back to the toilet.
Anderson's alleged accomplice rifled through the employees' personal property and asked the shift manager whether she wanted him to phone someone to inform them of the robbery so the hostages could be released.
The shift manager said she simply wanted both men to leave.
They left, but not before stealing her handbag containing her e-cigarette, tobacco, a bangle, a cellphone, torch charger, $125 cash, vehicle keys and an SD card, all valued at about $800.
The staff members freed themselves shortly after and contacted police. One employee suffered a minor laceration from the bindings.
About 7.30pm on June 1, police went to Anderson's house and found eight cannabis tinnies and $65 cash.
He admitted his role in the robbery and said he was paid $400 by an unknown person to help with the aggravated robbery. None of the stolen cash has been recovered.
One ring was recovered from the finger of his alleged accomplice's girlfriend.
Anderson will be sentenced on October 26.