Natural dye works / Porto / since 1954

# Fourteen dips to the bottom.

Plants, insects and iron. No synthetic correction, no boiling, and a published recipe for every colour that has ever left this building.

See the ladder
Four vats, one dyestuff. The steam is the only thing here that is not measured.

## One skein, fourteen times

The same wool, the same cochineal vat, dipped again and again. The mordant changes at the eighth, which is why the second rank turns towards plum instead of getting darker red.

1 Alum
2 Alum
3 Alum
4 Alum
5 Alum
6 Alum
7 Alum
8 Iron
9 Iron
10 Iron
11 Iron
12 Iron
13 Iron
14 Iron

A natural dye is not a colour you choose. It is a colour you arrive at, from a particular insect, in a particular water, at a temperature you hold for six hours, and the honest thing to do with the result is to number it and sell it as itself.

Purpurhaus has dyed on the Rua de Miragaia since 1954. Six of us, four vats, a drying loft, and a water supply we have had analysed every year since 1971 because the water is half the recipe.

We are not a natural alternative to industrial dyeing. We are a slower, more expensive and less repeatable process that produces colours industry cannot make, and that is the entire offer.

## Five steps

Two days of work and a fortnight of hanging still. The hanging is not waiting; it is part of it.

1. 01

   ### Scour

   Two hours in soda ash at a rolling simmer. Grease left in the fibre is the reason most dyeing goes patchy 2 h
2. 02

   ### Mordant

   Alum for the clear side of the range, iron for the sad side. The mordant, not the dye, decides what colour you get 4 h
3. 03

   ### Build the vat

   Cochineal, madder or logwood, brought up slowly and never boiled, because boiling takes the red out of everything 6 h
4. 04

   ### Dip

   Twenty minutes in, twenty minutes out in the air. The air is where the colour actually happens× 14
5. 05

   ### Wash and dry

   Rinsed until the water runs clear, then a fortnight on the rack out of direct sun 14 days

The loft. Out of direct sun, for two weeks, and no shortcut exists.
Ground and weighed. From here on, everything is arithmetic.

## Three refusals

Each one makes the work less repeatable, which is the point rather than the cost.

I

### Every recipe is published

Weights, temperatures, times and water. A recipe kept secret dies with the dyer, and this trade has lost more that way than it has to synthetics.

II

### Nothing is corrected

No synthetic top-up to hit a target, ever. If a batch comes out two dips lighter than the last it is sold as what it is, with its own number on the band.

III

### The vat is never boiled

Eighty-two degrees, held. Above that the reds go brown and there is no recovering them, which is one of very few things in this building that is genuinely irreversible.

## Ten dyestuffs

Everything in the store room. The mordant column is doing most of the work in this table.

1. Alum Cochineal Dactylopius coccus Insect, Canary Islands Crimson to rose
2. Iron Cochineal Dactylopius coccus Insect, Canary Islands Plum to aubergine
3. Alum Madder Rubia tinctorum Root, grown in Alentejo Brick to orange-red
4. Alum Logwood Haematoxylum campechianum Heartwood, imported Violet to purple
5. Iron Logwood Haematoxylum campechianum Heartwood, imported Near-black
6. Alum Weld Reseda luteola Whole plant, grown here Clear yellow
7. None Woad Isatis tinctoria Leaf, fermented vat Blue, by oxidation
8. None Walnut Juglans regia Hull, gathered Warm brown
9. Iron Oak gall Quercus infectoria Gall, imported Grey to black
10. Alum Onion Allium cepa Skin, from the market Ochre

> Anyone can match a colour. The difficult thing is admitting, in writing, that you did not.

> Idalina Freire, dyer

## Batches, numbered

Every band carries its batch number. When a batch is gone, that colour is gone with it.

1. PH-214 Cochineal on wool 14 dips, iron 4.2 kg Sold out
2. PH-211 Logwood on silk 9 dips, alum 1.8 kg 600 g left
3. PH-208 Madder on linen 6 dips, alum 6.0 kg 2.1 kg left
4. PH-204 Woad on wool Fermented vat 3.4 kg Sold out
5. PH-199 Cochineal on wool 7 dips, alum 5.1 kg 900 g left
6. PH-193 Oak gall on linen 4 dips, iron 2.7 kg Sold out
7. PH-188 Weld over woad 3 + 5 dips 1.2 kg 400 g left
8. PH-181 Walnut on wool 5 dips, none 8.8 kg Sold out

## Buying and learning

By the skein
  100 g skeins from the current batch, at the door and by post.
By the metre
  Linen and silk dyed to a batch, cut from the piece. Twelve metre minimum.
Commission
  Your fibre, our vat. Send a sample first; some wool simply will not take.
Teaching
  Four people at a time, three days, twice a year. It is mostly washing.

The dye house

+351 22 000 88 00

Rua de Miragaia 88, 4050 Porto. The recipe book is a PDF, it is free, and it is the only thing we send out the same day.

Monday
  Vats down
Tuesday
  09 – 17
Wednesday
  09 – 17
Thursday
  09 – 17
Friday
  09 – 15
Saturday
  By arrangement
Sunday
  Shut

An indigo vat is fed on Monday and left alone; anything dipped that day comes out the colour of an apology.