Just go to eldrich zone on crystal isles and look for big bubbles that have some black clams/oysters inside of them, put your angler fish inside the bubble, harvest, and enjoy the best black pearls harvester in the entire game, super easy, rank up for people to see this.

On the new map, Lost Island- there is a sunken ship in the very bottom left corner. I mean, tucked almost right in the corner, where the barriers meet. If you go inside the sunken ship, to the bottom of it, you will find clams full of only black pearls. The devs have a sense of humor, I'll give them that!

Pain in the ass to find on mobile

On Fjordur, the only way to obtain Black Pearls without going underwater is through, one, the Magmasaur den at the volcano in a cave inside the Fire Wyvern den, or two, from taming Gachas found in Asgard. Hope this helps anyone playing on the new map.

On the island map, this is such a pain to collect. Takes ages

Just become Jack Sparrow and summon Calypso

first tame an ichthy then go to rag about 75,23 more black pearls then you can carry on the sea floor and not to dangerous just keep an eye out for megs

When you want black pearls in great quantity, here are some things I suggest.

1: Ragnarok: Vikings bay. Bring a good crossbow to one shot any water scorpions, they drop TONS of black pearls.

2:Extiction: Gachas. Sometimes when taming gachas, you can get one that produces black pearls. They produce in big quantities, and for me is by far the safest and easiest way to get the black pearls. Like if this helps!😄

I just threw a my otter in water thinking I could get some fish meat but when I came to it, it gave me 30 pearls! I kept doing this until I got 230 pearls ands that’s how I got a tuso