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
Tyrian purple the purple". Some speculate that the dye extracted from the "Bolinus brandaris" is known as () in Biblical Hebrew. Another dye extracted from a related sea snail, "Hexaplex trunculus", produced a blue colour which could be the one known as (), used in garments worn for ritual purposes. The dye substance is a mucous secretion from the hypobranchial gland of one of several species of medium-sized predatory sea snails that are found in the eastern Mediterranean Sea. These are the marine gastropods "Bolinus brandaris" the spiny dyemurex, (originally known as "Murex brandaris" Linnaeus, 1758), the banded dye-murex "Hexaplex trunculus", the