I found an ‘alien-like’ goldmine washed up on the beach and it’s worth £4,000 – everyone is rushing out to find one

: “I found out they are Gooseneck barnacles, described as rare 'alien-like' sea creatures.

“They are said to be a delicacy, selling for more than £80 a kilo.”

Dave did not think to try and flog his interesting find and moved on to Snowdonia shortly after taking the snaps.

“At the time I posted the photos on Facebook without thinking them particularly newsworthy,” he said.

He also said he was anxious “not to create a stampede”.

The rare species of barnacle are enjoyed in countries such as Portugal and Spain, where they are called percebes with prices rising to up to £300 per kilo.

Each barnacle is worth around £2, which would make Dave's find worth up to around £5,000.

Those who have tried the delicacy say it tastes like a cross between lobster and clam, with a texture similar to octopus.

Dave’s discovery caused a stir on social media with many believing the creatures looked like something from another planet.

“Aliens have landed!!” said one woman.

While others urged him to “get collecting!”.

Despite his love of the area, Dave said he'd be reluctant to sample the fruits of his beach discovery.

“When you get close, you can see they are like small octopuses, or squid,” he said.

“They have tiny tentacles that reach out from their shells. I’ve never tried eating them and, having now seen them, I’m not sure I’d want to try.”