Bubble Coral Block
Bubble Coral Block is a vibrant purple coral block found in warm ocean biomes, and is part of the five colorful coral types alongside tube, brain, fire, and horn coral. It’s most often used for decoration, underwater building, and sea pickle farming thanks to its bright color and animation.
To obtain a bubble coral block in Survival mode, you must use a Silk Touch-enchanted pickaxe. Without Silk Touch, mining it will drop a dead bubble coral block, which is a gray, lifeless version. Bubble coral blocks naturally generate in coral reefs, and can also be bought from wandering traders for 3 emeralds each.
For a bubble coral block to stay alive, at least one of the six adjacent blocks must be water or waterlogged. If it’s not touching water, it will die after a few seconds, even if it’s underwater but completely surrounded by air or solid blocks. Once dead, it cannot be revived.
Live bubble coral blocks can also be used in sea pickle farms—placing sea pickles on top and using bone meal causes them to multiply and spread to nearby coral blocks. Additionally, when placed under note blocks, bubble coral blocks produce a 'bass drum' sound.