Mayor Peter Waterford who spoke on ABC radio about the find more than a week ago said there was a lot of potential because usually when one quality gem was found there would be more in the area.

"It could stretch out to be a $50 million patch."

Cr Waterford said he met the miner who showed him the specimen.

He said the miner was drilling in an area that had previously been mined but not for quite some time, when he stumbled across the large red on black gemstone.

"It's about 150 carats and I estimate it's worth around $200,000," Cr Waterford said of the significant find.

"It's the first opal I've seen of that size and calibre in a long time and it's created a lot of excitement among the miners in town.

"From what I've heard a lot of interest has been shown, more people have been coming into town in the past three months and this is just putting the icing on the cake," he said.

Meanwhile, mineral resources minister Kerry Hickey said if the reports were accurate, it was great news for the opal industry which was worth about $48 million a year and was vitally important to the region and the State's economy.

Mr Hickey said reports of the find at this stage were sketchy.

"The interest the reported find is generating is not surprising, we are world renowned for our quality black opals," he said.

"My department has spoken to the Walgett mayor (Peter Waterford) who is remaining very tight lipped over the location of the find and identity of the miners, we'll just have to wait and see."

Opal mining at Lightning Ridge has provided major benefits to the community and associated industries such as jewellery and tourism.

Nearly all rough opal produced is cut in Lightning Ridge with about 80 per cent exported principally to Japan, with other markets being the USA and Europe.