Calcareous Marine Algae
Calcareous marine algae is the collective term for several species of calcified red seaweed. Calcareous marine algae are very slow growing and can form extensive beds in favourable conditions, typically in relatively shallow and clear, unpolluted coastal waters where there is some tidal flow.
The live plant contains a pink pigment on its surface, which traps sunlight to provide energy for its growth. In time a dead, white calcareous skeleton develops which is rich in calcium and other minerals. It is only this dead material that is harvested from the seabed primarily for its significant value as an animal feed raw material and acidic soil conditioner.