The Lichen Dyes
Some of the most useful dyes and the least known are to be found among
the Lichens. They seem to have been used among peasant dyers from
remote ages, but apparently none of the great French dyers used them,
nor are they mentioned in any of the old books on dyeing. The only
Lichen dyes that are known generally among dyers are Orchil and
Cudbear, and these are preparations of lichens, not the lichens
themselves. They are
still used in some quantity and are prepared
rather elaborately. But a great many of the ordinary lichens yield
very good and permanent dyes. The Parmelia saxatilis and Parmelia
omphalodes, are largely used in the Highlands and West Ireland, for
dyeing brown of all shades. No mordant is needed, and the colours
produced are the fastest known. "Crottle" is the general name for
Lichens in Scotland. They are gathered off the rocks in July and
August, dried in the sun, and used to dye wool, without any
preparation. The crottle is put into the bath with a sufficient
quantity of water, boiled up, allowed to cool, then boiled up with the
wool until the shade required is got. This may take from one to three
or four hours, as the dye is not rapidly taken up by the wool. Other
dyers use it in the following way: A layer of crottle, a layer of
wool, and so on until the bath is full; fill with cold water and bring
to the boil, and boil till the colour is deep enough. The wool does
not seem to be affected by keeping it in the dye a long time. A small
quantity of acetic acid put with the Lichen is said to assist in
exhausting the colour.
The grey Lichen, Ramalina scopulorum dyes a fine shade of yellow
brown. It grows very plentifully on old stone walls, especially by the
sea, and in damp woods, on trees, and on old rotten wood. Boil the
Lichen up in sufficient water one day, and the next put in the wool,
and boil up again till the right colour is got. If the wool is left
in the dye for a day or more after boiling it absorbs more colour, and
it does not hurt the wool but leaves it soft and silky to the touch,
though apt to be uneven in colour. Some mordant the wool first with
alum, but it does not seem to need it.
The best known of the dye Lichens are Parmelia saxatilis and
Parmelia omphalodes which are still largely used in Scotland and
Ireland for dyeing wool for tweeds. The well-known Harris tweed smell
is partly due to the use of this dye.
Other Lichens also known for their dyeing properties are: Parmelia
caperata, or Stone Crottle, which contains a yellow dye, P.
ceratophylla, or Dark Crottle, and P. parietina, the common wall
Lichen, which gives a colour similar to that of the Lichen itself,
yellowish brown. A deep red colour can be got from the dull grey
friable Lichen, common on old stone walls. The bright yellow Lichen,
growing on rocks and walls, and old roofs, dyes a fine plum colour, if
the wool is mordanted first with Bichromate of Potash.
In Sweden, Scotland and other countries the peasantry use a Lichen,
called Lecanora tartarea to furnish a red or crimson dye. It is
found abundantly on almost all rocks, and also grows on dry moors. It
is collected in May and June, and steeped in stale urine for about
three weeks, being kept at a moderate heat all the time. The substance
having then a thick and strong texture, like bread, and being of a
blueish black colour, is taken out and made into small cakes of about
3/4 lb. in weight, which are wrapped in dock leaves and hung up to dry
in peat smoke. When dry it may be preserved fit for use for many
years; when wanted for dyeing it is partially dissolved in warm water;
5 lbs. of Korkalett is considered sufficient for about 4 Scotch ells
of cloth. The colour produced is a light red. It is used in the dyeing
of yarn as well as of cloth.
In Shetland, the Parmelia saxatilis (Scrottyie) is used to dye
brown. It is found in abundance on argillaceous rocks. It is
considered best if gathered late in the year, and is generally
collected in August.
Linnaeus mentions that a beautiful red colour may be prepared from the
Lichen Gyrophora pustulata. G. Cylindrica is used by Icelanders
for dyeing woollen stuffs a brownish green colour. In Sweden and
Norway, Evernia vulpina is used for dyeing woollen stuffs yellow.
Iceland Moss, Cetraria Islandica, is used in Iceland for dyeing
brown. Usnea barbata is collected from trees in Pennsylvania, and
used for an orange colour for yarn.
A general method for using lichens is suggested by Dr. Westring of
Sweden in his Experiments on Lichens for Dyeing Wools and Silks:
"The Lichens should be gathered after some days of rain,
they can then be more easily detached from the rocks. They
should be well washed, dried, and reduced to a fine powder:
25 parts of pure river water are added to 1 of powdered
lichen and 1 part of fresh quick lime to 10 parts powdered
lichen. To 10 lbs. lichen half a pound sal ammoniac is
sufficient when lime and sal ammoniac are used together. The
vessel containing them should be kept covered for the first
2 or 3 days. Sometimes the addition of a little common salt
or salt-petre will give greater lustre to the colours."
This method can be followed by anyone wishing to experiment with
Lichens.
Dr. Westring did not use a mordant as a rule. Where the same species
of Lichen grows on both rocks and trees, the specimens taken from
rocks give the better colours.
ORCHIL OR ARCHIL AND CUDBEAR are substantive or non mordants dyes,
obtained from Lichens of various species of Roccella growing on rocks
in the Canary Islands and other tropical and sub-tropical countries.
They used to be made in certain parts of Great Britain from various
lichens, but the manufacture of these has almost entirely disappeared.
They have been known from early times as dyes. They give beautiful
purples and reds, but the colour is not very fast. The dye is produced
by the action of ammonia and oxygen upon the crushed Lichens or weeds
as they are called. The early way of producing the colour was by
treating the Lichen with stale urine and slaked lime and this method
was followed in Scotland. Orchil is applied to wool by the simple
process of boiling it in a neutral or slightly acid solution of the
colouring matter. 3% Sulphuric acid is a useful combination. Sometimes
alum and tartar are used. It dyes slowly and evenly. It is used as a
bottom for Indigo on wool and also for compound shades on wool and
silk. For cotton and linen dyeing it is not used. It is rarely used by
itself as the colour is fugitive, but by using a mordant of tin, the
colour is made much more permanent.
Many of the British lichens produce colours by the same treatment as
is used for producing Orchil. Large quantities were manufactured in
Scotland from lichens gathered in the Shetlands and Western Highlands.
This was called Cudbear. The Species used by the Scottish Cudbear
makers were generally Lecanora tartarea and Urceolaria calcarea;
but the following lichens also give the purple colour on treatment
with ammonia:--Evernia prunastri, Lecanora pallescens,
Umbilicaria vellea, U. pustulata, Parmelia perlata. Several
others give colours of similar character, but of little commercial
value. The manufacture of Archil and Cudbear from the various lichens
is simple in principle. In all cases the plant is reduced to a pulp
with water and ammonia, and the mass kept at a moderate heat and
allowed to ferment, the process taking two or three weeks to complete.