Old Fustic

Fustic is the wood of Morus tinctoria, a tree of Central America. It

is used principally for wool. With Bichromate of Potash as mordant,

Old Fustic gives old gold colour. With alum it gives yellow, inclining

to lemon yellow. The brightest yellows are got from it by mordanting

with tin. With copper sulphate it yields olive colours (4 to 5 per

cent copper sulphate and 3 to 4 per cent tartar). With ferrous

sulphate darker olives are obtained (8 per cent ferrous sulphate). For

silk it does not produce as bright yellows as weld, but can be used

for various shades of green and olive. Prolonged dyeing should always

be avoided, as the yellows are apt to become brownish and dull.