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The extraction of indigo dye involves harvesting the small, green leaves of the Indigofera plant before its flowers bloom. These leaves undergo a process of soaking in water and churning until a navy blue froth is released. The upper portion of the resulting mixture is drained for irrigation, while the leaves are repurposed as fertilizer. After allowing the water and fine sediment to settle for a day, the liquid is separated from the sediment. The obtained deep blue paste is then subjected to filtration to remove dirt and impurities, followed by compression into cakes and drying for several days. Once dried, the indigo is ready for use as a dye. Lime (Ca(OH)₂) can be added to the initial water and leaves mixture, and various natural sugars can be dissolved into the paste to enhance the extraction process.