Similarly, you may ask, how does coral make limestone?
Coral reefs also consist of limestone that comes from organisms. However, in the case of reefs, the limestone is produced directly as coral organisms build their skeletons one on top of another. The shells get cemented together into limestone as some of their miner- als dissolve and re-form.
In respect to this, what are coral reefs made of?
A coral reef is made of thin layers of calcium carbonate Coral polyps form a living mat over a calcium carbonate skeleton. Stony corals (or scleractinians) are the corals primarily responsible for laying the foundations of, and building up, reef structures.
Coral Polyps — Tiny Builders Coral reefs are built by and made up of thousands of tiny animals—coral “polyps”—that are related to anemones and jellyfish.