Quercitron is the inner bark of the Quercus Nigra or Q. tinctoria, a
species of oak growing in the United States and Central America. It
was first introduced into England by Bancroft in 1775 as a cheap
substitute for weld. He says,
"The wool should be boiled for the space of 1 or 1-1/4 hours
with one sixth or one eighth of its weight of alum; then,
without being rinsed, it should be put int
a dyeing vessel
with clean water and also as many pounds of powdered bark
(tied up in bag) as there were used of alum to prepare the
wool, which is then to be turned in the boiling liquor until
the colour appears to have taken sufficiently: and then
about 1 lb. clean powdered chalk for every 100 lbs. of wool
may be mixed with the dyeing liquor and the operation
continued 8 or 10 minutes longer, when the yellow will have
become both lighter and brighter by this addition of chalk."
Flavin is extract of Quercitron bark, and is much used for bright
yellow with tin.
YELLOW (1 lb.)
Mordant with alum. Dye with 1 oz. Flavin.