Carrageenan is that the carrageenan is first dissolved and filtered to remove cell wall debris. The carrageenan is then precipitated from the clear solution either by isopropanol or by potassium chloride. A hybrid technology in which seaweed is treated heterogeneously as in the semirefined process exists, but alcohol or high salt levels are used to inhibit dissolution. This process is often used on South American seaweeds and gives some of the cost benefits of semirefined processing, while allowing a wider range of seaweeds to be processed, however, the naturally low cellulose levels in some South American seaweeds allow them to be
Purple Ages, those who dyed blue fabric and red fabric were members of different guilds, and were forbidden to dye any other colors than those of their own guild. Most purple fabric was made by the dyers who worked with red, and who used dye from madder or cochineal, so Medieval violet colors were inclined toward red. Orcein, or "purple moss", was another common purple dye. It was known to the ancient Greeks and Hebrews, and was made from a Mediterranean lichen called archil or dyer's moss (Roccella tinctoria), combined with an ammoniac, usually urine. Orcein began to achieve popularity again