Wednesday, April 28, 2010
Chay (Oldenlandia umbellata) as an alternative for madder.
In the Indian calico industries, madder root (as in various Rubia species) is sometimes replaced by the root of its relative, the Oldenlandia umbellata (Chay, chaia, chadar). It is considered to give a more brilliant red color (Sandberg 1994), in combination with calcium-high water and the exclusive use of stone mortars.
Eliot James, 1880: 'In the jury reports of the Madras exhibition considerable information on the subject of chay-root will be found, also on the Cherinji bark, and Jagi leaves, which of late years have been used in the place of chay-root dye, and have indeed very nearly superseded its use, though not possessing its claims to brilliancy of colour and durability of effect'.
In contrast to regular madder, Oldenlandia contains no purpurin, just alizarin. Hofenk de Graaff (1992) mentions the occurence of rather large amounts of yellow crystalline elements that tend to dissolve tanning substances. This can be remedied by adding bases. This would also explain why Oldenlandia (she mentions Saya wera as name) from coastal areas is considered superior, as the destroying acids would have already been neutralised there. The same goes for the calcium/high water.