MIAMI — A man was out on bond in four separate cases in Miami-Dade County when he went to a downtown Miami jewelry store and tricked sales staff into giving him a $14,000 diamond ― which he never gave back ― according to police, court and jail records.
Robert Holmquist, 30, of Key Biscayne, is now back in jail on another grand theft charge after his latest arrest on Monday.
According to Miami police, the theft happened as Holmquist was dealing with a jeweler at the Seybold Jewelry Building, located at 36 NE First St., on Jan. 16. An arrest report doesn’t state in what capacity, but it implies that the jeweler believed that Holmquist was working as a legitimate vendor or middleman.
The report states that the jeweler showed Holmquist a two-carat diamond worth $14,000. It states that Holmquist told the jeweler “he was going to take the diamond to a nearby unit at the (building) to see if he could sell it” and would “return within a few minutes.”
He “did not return” and the jeweler was left texting and calling Holmquist to no avail, according to police.
Authorities said they arrested Holmquist Monday afternoon in the area of Southwest 117th Avenue and 152nd Street.
It adds to his list of pending cases which stem from 2025 arrests by the Miami-Dade Sheriff’s Office. In two June incidents, he was accused of stealing Dyson hair dryers and vacuum cleaners worth thousands of dollars from a Target at 7795 Bird Road and a Costco at 7795 W. Flagler St.
Also in June, he was also accused of stealing more than a dozen bottles of wine from the Target at 10101 W. Flagler St.
According to court records, the most serious allegations against Holmquist stem from an incident on Aug. 13 at the Advance Auto Parts at 8345 S. Dixie Highway, near Dadeland Mall.
According to an MDSO arrest report, Holmquist walked into the store and asked for a can of freon, left, then “abruptly came back in,” saying the can was empty and that they “need(ed) to give him another one.”
Authorities said when a store worker refused, Holmquist pushed a shopping cart into his groin, “causing great bodily harm.”
The report states that when the worker threw a can of freon at him in self-defense, Holmquist told him, “I’m gonna blow your head off” and pulled a gun on the worker, prompting the worker to call 911.
Deputies arrested Holmquist on charges of aggravated battery and aggravated assault with a firearm, as well as a drug charge for allegedly having several pills in an unmarked bottle. Court records show the drug charge was later dropped.
He would be formally arrested on grand theft charges in the other cases while locked up at the Turner Guilford Knight Correctional Center.
He’s now back at TGK as of Tuesday morning. Considering the pending cases, his bond status wasn’t immediately clear.
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