He had no idea the pearl, which is five times larger than the previous record, was worth an eye-watering value of $100 million.
A fire at his wooden home earlier this year forced him to move house and he decided to have it in to the stunned local tourism officer in remote Puerto Princesca.
They were able to verify that it had been found in a giant clam.The priceless rock measures a staggering 1ft foot wide and 2.2 feet long - dwarfing the current world's biggest Pearl of Allah which weighed 6.4kg and is worth $35million.
Tourism officer Aileen Cynthia Amurao said:
'The fisherman threw the anchor down and it got stuck on a rock during a storm.'He noticed that it was lodged on a shell and swam down to pull up the anchor, and also brought the shell with him. This was a decade ago and he kept it at home.'He didn't know how much it was worth and kept it tucked away at home as a simple good luck charm.
'We were amazed when he brought it to us. We now need help from gemologists to fully certify it. We're waiting for authentication from Gemologist Institute and other international authorities.
'But we believe Puerto Princesca is likely earn another prestigious title and a record breaker for having the world's biggest natural giant pearl from a giant clam.We will keep this here in the Philippines and I hope it will bring more tourists to the city.'The gem was shown off to the public today.
Source: The Sun UK