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Irish moss, or carrageen moss (Irish: carraigín, "little rock"), is a species of seaweed which grows abundantly along the rocky parts of the Atlantic coast of Europe and the Americas as well as parts in the Pacific. In its fresh condition the plant is soft and cartilaginous, varying in color from a greenish-yellow, through red, to a dark purple or purplish-brown. The principal constituent of Irish moss is a mucilaginous body, made of the polysaccharide Carragenan of which it contains about 55%; the plant also has nearly 10% of protein and about 15% minerals, specifically rich in iodine and sulfur. Because of the abundant cell wall polysaccharides it will form a jelly when boiled or processed with water expanding from 20 to 100 times of its weight.