Kappaphycus alvarezii Kappaphycus alvarezii Kappaphycus alvarezii, the elkhorn sea moss, is a species of red algae. It is one of the most important commercial sources of carrageenans, a family of gel-forming, viscosifying polysaccharides. Farming methods affect the character of the carrageenan that can be extracted from the seaweed. This alga grows to two meters long and is green or yellow in color. It is very fast-growing, known to double its biomass in 15 days. Different carrageenan types differ in composition and conformation, resulting in a wide range of rheological and functional properties. Carrageenans are used in a variety of commercial applications as
Purple of the Emperor Justinian in Ravenna. The chemical composition of the dye from the murex is close to that of the dye from indigo, and indigo was sometimes used to make a counterfeit Tyrian purple, a crime which was severely punished. What seems to have mattered about Tyrian purple was not its color, but its luster, richness, its resistance to weather and light, and its high price. In modern times, Tyrian purple has been recreated, at great expense. When the German chemist, Paul Friedander, tried to recreate Tyrian purple in 2008, he needed twelve thousand mollusks to create 1.4 ounces