Coral Block

Coral blocks are solid blocks that come in five variants: tube, brain, bubble, fire, and horn.

Dead coral blocks are the dead variants of coral blocks.

Obtaining
Coral blocks can only be obtained with a pickaxe enchanted with Silk Touch, otherwise, they will drop the respective dead coral block. Dead coral blocks can be obtained with any type of pickaxe.

Natural generation
Coral blocks and dead coral blocks naturally generate in coral reef structures. These are found in warm oceans.

Trading
Coral blocks can be bought from wandering traders for 3 emeralds.

Usage
Coral blocks and their dead variants can be used as building or decoration blocks.

Sea pickle farm blocks
Coral blocks grow sea pickles when bone meal is used on it. Additionally, if sea pickles are planted on coral blocks, using bone meal on the sea pickles will increase the number of sea pickles, and create more sea pickles on nearby coral blocks. Specifically, they can spread to the original sea pickle's level or one level below, out to a horizontal taxicab distance of 2. These are the only ways for farming renewable sea pickles.

Dead coral blocks
In order for coral blocks to stay alive, at least one of the orthogonally-adjacent blocks must be water. If placed outside of water, it will transform into its respective dead coral block after a few seconds. They are a grayscale version of coral blocks.

Block data
In Bedrock Edition coral blocks have the following block data:

Trivia

 * After players had placed 10 million coral blocks underwater $$, Mojang donated US$100,000 to The Nature Conservancy to protect and restore coral reefs around the world.