In their investigation, police said a man entered the store and asked to take a look at a ring worth about $2,400.
Jeweler Tony Farwell told KIRO on Thursday the ring was worth $1,800.
"Once the suspect had possession of the ring, he fled out of the business and advised the business owner that he had a gun," a spokesperson for the police department wrote in a news release.
Police said Farwell chased the man outside of the business, drew his weapon and demanded the man to stop.
According to police, the man displayed what was later determined to be a BB gun but never pointed the gun at Farwell.
A witness then helped in detaining the suspect until police could arrive, officials said.
The man was taken into custody and was booked into the Thurston County Jail on investigation of robbery.
Officials said the ring was recovered and is available for sale.