The screwdriver was used to unscrew a display case sometime on Saturday at the Cloncurry Unearthed Visitor Information Centre and Museum. 

Eleven of the taken samples were fluorite, but others included tournmaline, calcite and malachite. 

The thief appears to have picked and chosen the minerals, having ignored closer exhibits for ones further away. 

According to these exhibit tags, the minerals were found in Mount Isa, Cloncurry, Quamby and at Mary Kathleen.

Cloncurry Police Station officer-in-charge Senior Sergeant Brad Rix confirmed that the theft happened during daylight hours. The minerals had no set value, he said. 

“It’s hard to put a price on it. They’re not really replaceable,” he said. 

Senior Sergeant Rix said the thief knew what they were doing and was selective in what was stolen.

“It was not an opportunistic thing. They’ve made the effort to get into the cabinet by unscrewing some screws,” he said.

Police did not know who the thief could be, and investigations were continuing. 

Cloncurry Shire Council chief executive David Neeves said the council would make the museum exhibits more secure.

“Council is implementing measures to make sure it won’t happen again,’’ he said.

“We’re now looking at a locking mechanism.”

The mechanism will prevent potential thieves from unscrewing the display cases with screwdrivers. 

The Cloncurry Shire Council was “disgusted” at the act. The minerals were kept in the museum for the benefit of tourists and the community, Mr Neeves said.

He said the council was attempting to replace the exhibits.

“We’re researching now where we can source alternative sources,” he said.

Mount Isa fossicker Jim Adlington said the stolen minerals were likely to be in a private collection somewhere.

But if minerals matching the description of the stolen exhibits appeared on eBay, he would “put the word out”.

As a fossicker, he saw little value in the minerals stolen but a collector might think otherwise. 

“I can’t see much value in the whole lot,” he said. 

Fluorite was increasingly becoming more difficult to find, even in Cloncurry where it was known to be more common.

Mr Adlington said there were two types of tourmaline that might have been among the exhibits. The coloured variety could be considered rare but the black shoal type was not valuable at all.

Perhaps not coincidentally, Mr Adlington was recently asked by a man where fluorite could be found in the area. 

The Cloncurry Shire Council said it would investigate further security measures for the building, which may include security cameras, alarm systems or sensor lighting. 

On the day of the theft, there were 78 recorded visitors to Cloncurry Unearthed.