Old Fustic
A Guide to Old Fustic
Shepherd Textiles Old Fustic Natural Dye contains the chipped heartwood of maclura tinctoria, a mulberry tree native to tropical regions of the Americas. For centuries Old Fustic was one of the most important of the natural yellow dyes, as well as a common ingredient in compound colors like black and brown. It contains a pigment called morin that gives beautiful yellow and yellow-orange shades. Our Old Fustic chips are high-quality heartwood sourced from Brazil. They will produce clear lemon yellows using 40% weight-of-fabric, or rich golden yellows at 100% weight-of-fabric. Please note that Old Fustic chips produce good results on wool and silk, but for cotton we recommend using Old Fustic Extract instead.
1. Background on Old Fustic
The Old Fustic tree maclura tinctoria (also known as chlorophora tinctoria or morus tinctoria in some sources) is a member of the mulberry family native to the tropical Americas. It can be found growing from Mexico to Brazil, as well as on many of the Caribbean islands. Old Fustic began to be exported to Europe for use as a dye sometime in the 17th century, and it quickly became one of the most important colors in the dyer’s repertoire. Properly dyed, Old Fustic gives clear yellows and golden shades with good fastness and intensity. The wood was especially esteemed in England, where thousands of tons were imported every year for the purpose of dyeing yellow (Gardner 1896:46). On the Continent it was somewhat less popular for dyeing yellow than locally grown weld, and in the United States quercitron (black oak bark) was the preferred yellow, but Old Fustic was always in high demand because it is an essential ingredient in compound colors like logwood black and cochineal scarlet. The use of Old Fustic declined around the turn of the century, partly because coal-tar colors were increasing in popularity and partly because the natural sources were being over-logged and exhausted. As late as 1914, however, thousands of pounds of Old Fustic were imported into the United States to dye military uniforms their classic khaki shade.
Old Fustic contains two primary dyestuffs, morin and maclurin (also known as moritannic acid) (Crookes 1874:406). Morin and maclurin behave differently in the dyebath and have different effects on the final color. Morin is responsible for the desirable yellow and orange shades that develop with an alum mordant (Gardner 1896:48). Maclurin, on the other hand, behaves like a tannin and tends to produce drab browns. This makes getting clear yellow shades with Old Fustic somewhat tricky, because if the dyebath gets too hot or if the fiber is left in it too long the maclurin can begin to overpower the morin and the color will become muddied and dull. For that reason, Old Fustic is best dyed between 180F and 190F - pushing the temperature much higher risks disaster. In the past, dyers would actually add hide glue to the dyebath in an effort soak to up some of these excess tannins if they needed to dye at a higher temperature. An easier alternative today is to use Old Fustic Extract, since the excess tannins have been removed during the extraction process.
Old Fustic is one of a handful of dyes that respond well to “single-bath” methods in addition to the standard pre-mordanting method. Single-bath colors will often come out clearer, although the trade-off is that they may require a bit more of the dye to get the same depth of shade. This guide presents several ways of dyeing with Old Fustic, many adapted from professional dyeing texts from the 19th century.
The Tropical Yellow
2. Safety Precautions
DO NOT INGEST. This product is intended for textile dyeing, not as an herbal supplement.
Avoid eye contact. If eye contact occurs, rinse with cool water.
Not for use as a cosmetic additive; do not apply directly to skin or hair.
Open carefully to avoid spilling or creating dust. Work in a well-ventilated space, and avoid inhaling sawdust. Wear a mask if necessary while working with fine powders.
If a spill occurs, quickly wipe up with a paper towel or disposable rag.
Use only dye pots and utensils dedicated to dyeing. Do not use any pots, containers, spoons, tongs, thermometers, or other utensils that will be used for food preparation.
Old Fustic shavings, and all dye baths and mordant liquors made while dyeing, should be kept out of reach of children and pets. Use only with adult supervision.
Several recipes in the guide require the use of oxalic acid. Oxalic acid is highly caustic and poisonous if ingested. Do not attempt these recipes without an outdoor dyeing setup and proper safety gear; read our precations and your manufacturer’s SDS (Safety Data Sheet) first.
Prop 65 Warning: The product contains wood dust, which is known to the State of California to cause cancer.
Shepherd Textiles, LLC is not liable for any misuse of this product or any unintended staining of your clothing, workspace, or other property. Use only as directed.
3. Recommended Supplies
Dye pot. Use a dye pot large enough to hold all your fibers, with plenty of room for them to move around and for the liquid to circulate freely.
Metal tongs. A pair of tongs is useful for stirring and taking fabric out. Use tongs dedicated to dyeing, and not for food preparation.
Rubber gloves. Wear rubber gloves while handling mordanted/dyed fiber before it has been rinsed.
Candy thermometer. The best way to keep track of temperature is to use a candy thermometer that clips to the side of the dye pot.
Scale. Use a scale to weigh out fiber, mordant, and dyestuff.
Alum mordant. The alum usually used for mordanting is aluminum potassium sulfate, also known as potash alum. It is the same alum that you can find in a jar in the spice section at the grocery store.
Tin mordant. Sold as “stannous chloride,” tin is used in combination with alum to get brighter yellows with Old Fustic.
Fine mesh strainer. For straining out the wood after extraction.
4. Preparation: Scouring and (Not) Mordanting
Old Fustic is one of those rare natural dyes that gives equally good results from both “single-bath” recipes and the standard pre-mordanting method. Single-bath recipes tend to require a bit more weight of wood for the same depth of shade, but they can also produce clearer yellows. For that reason, we generally do not pre-mordant the fiber when dyeing with Old Fustic chips (although if you prefer to pre-mordant, you can use 10% alum and 11% cream of tartar for a good yellow). The fiber should, however, be well-scoured (cleaned) and wetted out before going into the dye bath.
For protein fibers (wool, silk, alpaca, etc.): Scour well before dyeing.
Weigh out the fibers you plan to dye (while they are dry) so you can calculate the amount of wood chips and mordant you will need later.
Unless your fibers are already very clean, they will need to be scoured (cleaned). A basic scouring can be done with a small amount of pH-neutral detergent. Fill a dye pot with warm tap water, leaving enough room for the fiber to move around freely. Add 1/2 tsp of pH-neutral detergent like Synthrapol or Orvus Paste per pound of fiber to be cleaned. Mix well and add the fibers to the pot. Raise the heat to 180°F for wool or 160°F for silk. Maintain the heat for one hour, stirring occasionally so the fibers are cleaned evenly. After an hour, take the pot off the heat and allow it to cool until the fiber can safely be handled. Using tongs, transfer the fiber to a rinsing bath that is the same temperature as the scouring bath it just came out of (to prevent temperature shocks that could cause wool to felt). Rinse well, and proceed to dyeing.
For cellulose fibers (cotton, linen, etc.): Use Old Fustic Extract instead.
Old Fustic wood itself gives unexciting results on cellulose fibers like cotton, even if the cotton has been properly tanned and mordanted prior to dyeing. Historically, Old Fustic was applied almost exclusively to wool and silk, and when it was applied to cotton it was generally as a component of compound colors like brown (see, e.g., Hummel 1902:359). To apply Old Fustic to cotton or other plant-based fibers, we recommend using our Old Fustic Extract instead, which is highly concentrated and gives beautiful golden yellow shades on cotton.
5. Preparation: Building the Dye Bath
Building a dye bath with Old Fustic chips is very easy and simply requires simmering the color out of the wood. Some dyers like to soak the chips for lengthy periods of time before extracting them, and then boil them multiple times to get as much color out as possible. However, we find that two short extractions of about half an hour each will get nearly all the color out of the wood. This shorter process will also help minimize the extraction of tannins and make it easier to dye clear, vibrant shades of yellow.
Step 3. Old Fustic gives up its color more slowly than other dye woods - the dye bath will not really start turning orange until it is boiling.
Step 5. Filter the extraction liquid through cheesecloth or a fine mesh strainer to get out any wood bits.
Weigh out the quantity of Old Fustic chips called for in your recipe.
Put the Old Fustic in your dye pot and fill it about 1/2 full with lukewarm water.
Bring the bath to a rolling boil. Lower the heat, cover, and simmer for 20 minutes.
Turn off the heat and let the chips steep for 10 more minutes. Then, uncover the pot and let the liquid cool until it is safe to handle.
Filter the orange dyebath liquid into a holding container, like a plastic bucket or a second dye pot. Strain it through a cheesecloth, an old t-shirt, or a very fine mesh sieve; any wood that makes it into the final dyebath can cause splotches on your fabric.
Return the strained wood to the dye pot and fill it about 1/2 full with lukewarm water again. Repeat steps 3 through 5. When you are finished, add the second extraction to the first one.
[Optional] If you think there might still be some color left in the wood you can repeat steps 3 through 5 again, but often when we have tried a third extraction the water comes out mostly clear.
Dispose of the wood and clean out your dye pot. Pour the combined extractions back into it. This dark orange liquid will be your dye bath.
The Recipes
6. Recipe: Lemon Yellow
This recipe is adapted from Franklin Beech’s “The Dyeing of Woolen Fabrics,” published in 1902. It gives a clear lemon yellow on wool and silk that has a pleasant pastel tone, rather than the bright neon yellow that some other natural dyes produce. The fiber should be well-scoured and wetted before going into the bath.
Build a dyebath, as described in Section 5, using 40% weight-of-fabric (WOF) of Old Fustic chips.
After straining the wood out of the dyebath, add 6% WOF cream of tartar and mix well*.
Add 6% alum and 2% tin (stannous chloride). Mix well for a minute or so until everything is dissolved.
Add your well-scoured, wetted fiber to the dyebath.
Raise the temperature to 180°F for silk or 190-200°F for wool, then maintain for 1 hour. Stir occasionally to make sure everything dyes evenly.
After 1 hour, remove pot from heat and allow to cool until the fiber can be safely handled.
Remove the fibers and rinse briefly in warm water. Hang them up to dry to help the color set; make sure to hang them up in the shade somewhere where dripping dye will cause no damage. Direct sunlight may fade the color before it has had time set.
For the final rinsing, we recommend using a PH-neutral detergent like Synthrapol that is designed to wash out loose dye. Follow the manufacturer’s directions for best results. CAUTION: Old Fustic may bleed if not thoroughly rinsed out after dyeing.
Hang up to dry.
*Note: Whenever you are using a single-bath recipe, always add the cream of tartar (or oxalic acid) before the mordants to prevent them from combining with the dye and precipitating prematurely - otherwise some of the dye may be wasted.
7. Recipe: Golden Yellow
Using the same recipe as above but increasing the concentration of Old Fustic chips to 100% weight-of-fabric deepens the color from a lemon shade to a rich golden yellow. The combination of tin and alum mordants balances the color nicely and gives it a good warmth without developing too much orange.
Build a dyebath, as described in Section 5, using 100% weight-of-fabric (WOF) of Old Fustic chips.
After straining the wood out of the dyebath, add 6% WOF cream of tartar and mix well*.
Add 6% alum and 2% tin (stannous chloride). Mix well for a minute or so until everything is dissolved.
Add your well-scoured, wetted fiber to the dyebath.
Raise the temperature to 180°F for silk or 190-200°F for wool, then maintain for 1 hour*. Stir occasionally to make sure everything dyes evenly.
After 1 hour, remove pot from heat and allow to cool until the fiber can be safely handled.
Remove the fibers and rinse briefly in warm water. Hang them up to dry to help the color set; make sure to hang them up in the shade somewhere where dripping dye will cause no damage. Direct sunlight may fade the color before it has had time set.
For the final rinsing, we recommend using a PH-neutral detergent like Synthrapol that is designed to wash out loose dye. Follow the manufacturer’s directions for best results. CAUTION: Old Fustic may bleed if not thoroughly rinsed out after dyeing.
Hang up to dry.
Note: Do not let the temperature of the dyebath climb past 200°F - higher temperatures encourage the tannins to develop and the color of the fiber may start to become dull and brown.
8. Recipe: Tin Yellow
This recipe takes advantage of the synergy between oxalic acid and tin, which produce bright colors when they are combined together in a single bath. It produces a slightly lighter shade than the previous recipe when the same amount of wood is used, but the yellow is very clear. This is how professional dyers would have applied Old Fustic in the 19th century. However, note that oxalic acid is highly caustic and harmful if inhaled. Read the precautions first, and do not attempt this recipe unless you have an outdoor dyeing setup (to help fumes disperse) and a full respirator mask!
Build a dyebath, as described in Section 5, using 40% (for a pastel yellow) or 100% (for a golden yellow) weight-of-fabric (WOF) of Old Fustic chips.
After straining the wood out of the dyebath, add 4% WOF oxalic acid and mix well**.
Add 5% tin (stannous chloride). Mix well for a minute or so until everything is dissolved.
Add your well-scoured, wetted fiber to the dyebath.
Raise the temperature to 190-200°F and maintain for 1 hour. Stir occasionally to make sure everything dyes evenly, and don’t let the temperature go much past 200°F. Keep the lid on when possible, and wear a respirator and eye protection when opening the pot to stir or check the temperature.
After 1 hour, remove pot from heat and allow to cool until the fiber can safely be handled.
Remove the fibers with tongs and rinse well in lukewarm water. Be sure to wear rubber gloves while handling it until it is rinsed - a good rinsing will neutralize any remaining acid. Hang the fiber up to dry to help the color set; make sure to hang it up in the shade somewhere where dripping dye will cause no damage. Direct sunlight may fade the color before it has had time set.
For the final rinsing, we recommend using a PH-neutral detergent like Synthrapol that is designed to wash out loose dye. Follow the manufacturer’s directions for best results. CAUTION: Old Fustic may bleed if not thoroughly rinsed out after dyeing.
Hang up to dry.
**Caution: Oxalic acid is toxic if ingested and can cause chemical burns if it touches the mucuous membranes. Do not ingest; avoid contact with skin, eyes, mouth, and nose. Do not inhale fumes from the hot dye bath. Wear gloves when handling the dye bath or fiber coming out of the dye bath until it has been well rinsed. If ingestion or inhalation occurs, contact a poison control center immediately. Read your manufacturer’s SDS (Safety Data Sheet) before using oxalic acid and observe all recommended safety precautions. Do not attempt this recipe unless you have an outdoor dyeing setup and full protective gear, including rubber gloves, eye protection, and a respirator mask (this is the one we use). Dispose of the spent dye bath safely according to local regulations. Store oxalic acid and any dye baths containing oxalic acid away from children and pets.
9. Recipe: Not-Quite-Scarlet
The combination of tin and oxalic acid in a single bath is famous because it is the foundation for Cochineal Scarlet, perhaps the most intense color that natural dyes can produce. A small amount of Old Fustic is usually added when dyeing scarlet to increase the fiery quality of the red. However, the proportion of Old Fustic to cochineal can be adjusted to yield a variety of shades, from salmon to orange. We give two examples below, but feel free to play with the proportions to your liking.
Build a dyebath as described in Section 5. For a salmon shade, use 50% weight-of-fabric (WOF) of Old Fustic chips and add 1% WOF of ground cochineal along with the wood. For bright orange, use 100% WOF of Old Fustic chips and 0.25% WOF of cochineal (you may want to put the ground cochineal in a tea bag to make it easier to strain out after the extraction).
After straining the wood and cochineal out of the dyebath, add 4% WOF oxalic acid and mix well**.
Add 5% tin (stannous chloride). Mix well for a minute or so until everything is dissolved.
Add your well-scoured, wetted fiber to the dyebath.
Raise the temperature to 190-200°F and maintain for 1 hour. Stir occasionally to make sure everything dyes evenly, and don’t let the temperature go much past 200°F. Keep the lid on as much as possible, and wear a respirator and eye protection when opening the pot to stir or check the temperature.
After 1 hour, remove pot from heat and allow to cool until the fiber can safely be handled.
Remove the fibers with tongs and rinse well in lukewarm water. Be sure to wear rubber gloves while handling it until it is rinsed - a good rinsing will neutralize any remaining acid. Hang the fiber up to dry to help the color set; make sure to hang it up in the shade somewhere where dripping dye will cause no damage. Direct sunlight may fade the color before it has had time set.
For the final rinsing, we recommend using a PH-neutral detergent like Synthrapol that is designed to wash out loose dye. Follow the manufacturer’s directions for best results. CAUTION: Old Fustic may bleed if not thoroughly rinsed out after dyeing.
Hang up to dry.
**Caution: Oxalic acid is toxic if ingested and can cause chemical burns if it touches the mucuous membranes. Do not ingest; avoid contact with skin, eyes, mouth, and nose. Do not inhale fumes from the hot dye bath. Wear gloves when handling the dye bath or fiber coming out of the dye bath until it has been well rinsed. If ingestion or inhalation occurs, contact a poison control center immediately. Read your manufacturer’s SDS (Safety Data Sheet) before using oxalic acid and observe all recommended safety precautions. Do not attempt this recipe unless you have an outdoor dyeing setup and full protective gear, including rubber gloves, eye protection, and a respirator mask (this is the one we use). Dispose of the spent dye bath safely according to local regulations. Store oxalic acid and any dye baths containing oxalic acid away from children and pets.
All images and text are copyright of Shepherd Textiles, LLC. Do not reproduce without written permission and attribution.