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.