With the release of Minecraft 1.13 the game is undergoing some pretty big changes including the introduction of custom crafting recipes and coral reefs.
Currently coral blocks and their variants are not renewable resources which means the reefs will be heavily mined away until they are go. If you are anything like me, you hate ruining biomes for their resources, so instead I created this datapack.
Coral is supposed to be rare so the recipe takes a little work to gather nautilus shells, but the rest of the ingredients are easy.