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 is a spectral color. On the CIE xy chromaticity diagram, violet is on the curved edge in the lower left, while purples are on the straight line connecting the extreme colors red and violet; this line is known as the line of purples, or the purple line. During the Middle Ages, artists usually made purple by combining red and blue pigments; most often blue azurite or lapis-lazuili with red ochre, cinnabar, or minium. They also combined lake colors made by mixing dye with powder; using woad or indigo dye for the blue, and dye made from cochineal for the red.