Period leather dyes?

[John S.]

Harry, are you interested in checking for color fastness of any of these dyes?

A possible protocol would be:
*Cut each sample in 3 pieces.
*First piece is a control.
*Second piece gets wiped briskly with a wet rag and left to dry.
*Third piece gets soaked in a water bath for ____ time and then dried.

Bonus points for documenting both:
*Any color transfer to the wet rag or water bath, and
*Any color change to the samples.

[John S.]

Oh, and depending on how you write it up, what you're doing could verge on a publishable academic paper. Some of the pro's on the archive could probably suggest possible journals.

[Harry Marinakis]

John,
Color-fast and sun-fast tests are on the agenda, but not at this early stage in the game. Those test will be performed as the very last set of experiments in this project.

[Harry Marinakis]

Here is another experiment with Madder root and chalk.

Adding chalk is supposed to brighten the color, so I added chalk at 2%, 5%, 10% and 20% WOL.

Looks like a little chalk is good, too much chalk stains the leather.

Tin @ 3% WOF apparently improves the color when dyeing fiber with Madder - like adding chalk - but apparently tin @ 3% WOL prevents dyeing of leather!

Footnote: Tin @ 3% WOL turns leather yellow!

[Harry Marinakis]

Here is a really nice colorfast red that I got from Red Sandalwood, or Padauk.

Padauk is a red African wood. I got this 2" x 2" x 12" turning block for $6.

The colorant can be extracted by boiling in water, but I used denatured alcohol that I bought at Home Depot. The ratio that I used was 350 ml of denatured alcohol for 20 grams of Padauk shavings. I let the Padauk shavings soak in the alcohol for 24 hours, and then decanted the solution. This was my dye.

I did not even use a mordant - this is what I got with a 24-hour soak in the Padauk extract.

The leather swatch shown here is 2.5" x 4"

The dye is very colorfast; I tried to wipe off the dye with a wet white rag but got nothing.

[Mac]

You are doing good work here, Harry!

It's far enough outside my expertise that I don't have anything useful to say, but I recognize good work when I see it.

Bravo!

Mac

[CTrumbore]

Here is a really nice colorfast red that I got from Red Sandalwood, or Padauk.

Padauk is a red African wood. I got this 2" x 2" x 12" turning block for $6.

The colorant can be extracted by boiling in water, but I used denatured alcohol that I bought at Home Depot. The ratio that I used was 350 ml of denatured alcohol for 20 grams of Padauk shavings. I let the Padauk shavings soak in the alcohol for 24 hours, and then decanted the solution. This was my dye.

I did not even use a mordant - this is what I got with a 24-hour soak in the Padauk extract.

The leather swatch shown here is 2.5" x 4"

The dye is very colorfast; I tried to wipe off the dye with a wet white rag but got nothing.

Its going to turn brown with uv exposure. Also.. padauk is an irritant (most of the sandalwoods and cinnamons are) so use caution around its airborne dust.

[Harry Marinakis]

Follow up on the Padauk dye, after the leather sat out on the back porch for 2 days.

The top half of the image is the backside of the leather that was not exposed to the sun. The original color was more of a salmon than a true red.

The bottom half of the image is the sun-exposed side of the leather.

[Harry Marinakis]

Continuing on with the saga....

I made a Brazilwood leather dye, using recipe #16 from the Plictho (AD 1540):

"Measure brazil thinly shredded 1 ounce, common water 1 pound, of fish glue, half ounce, roche alum 2 ounces, which water keeps many years. Put to soak the before said things in the said water for three days. Then make them boil in a glazed vessel, and make it stay covered until it reduces by half and it will become very perfect brazil.”

The quantities from medieval Italy are not the same as today, so with a bit more research I came up with these numbers, converted to modern weights:

Brazilwood 1 ounce = 40 grams
Water 1 pound = 477 ml (12 ml per gram of Brazilwood)
Fish glue half ounce = 20 grams
Roche alum 2 ounces = 80 grams

The roche alum is acidic in aqueous solution (pH = 4), so it shifts the Brazil color towards a brilliant red.

This dye is pretty dilute - 40 grams of Brazilwood extract in 235 ml of water (or 0.17 gm/ml). After using this dye, I would make it 2 or 3 times more concentrated than this.

But I really don't like this recipe - there is so much roche alum in the dye that when it dries the leather sparkles from all the roche alum crystals, like it's covered in glitter.

[Harry Marinakis]

Then I went onto Plictho recipe #165, which uses brazil extract to dye leather:

"Take the hide and put it into warm water, that is tepid. See that there is enough water to cover the hide and wring it so that the said hide becomes soft. Return again into said water for half an hour. Then take it out and set it to dry and watch that it does not dry out too much. Then when dry, knead it with the hands so that it becomes good and soft. Then take a stone of pumice to take off the air and then beat the hide that you want to dye. For each pound of hide give it two ounces of roche alum. See that said alum stays in as much as suffices to wet the said skin, and you make the roche alum dissolve well. Then set the said hide in said water and each time you wet it set it to dry. You will do thus until the said hide receives all the said water and when you are at the last time, take off the hair with coarse pumice. Then take enough “brasilio” that suffices and give it with a brush, three or four times. See when cook the brazil that it needs a change of hot water and the other you make boil so such that the brazil is cooked. Then you dye and you will see your skin dyed and beautiful."

This is an interesting recipe because it gives hard numbers - "For each pound of hide give it two ounces of roche alum." This converts to 17% WOL.

I used the Brazil dye made from Plictho recipe #16.

I applied 6 coats of dye to the leather, but the results were somewhat disappointing. All I got was a reddish brown.

[Harry Marinakis]

Plictho recipe #166 - "To Dye Skins or Hides in Morello Color"

This recipe turned out to be a bit more interesting. It's a recipe to dye skins a wine (morello) color.

"Measure a little live lime and put it into the brazil and give it the first hand of color written, and this makes a morello. Keep in mind that when you wash the skin of goat or of whatever sort it is, as long as it is tanned, have in mind to wring it and smooth it so that it be will be more soft.”

This recipe uses quicklime to shift the pH more alkaline, into the purple color range of Brazil. Since quicklime violently reacts with water to form a slacked lime, I simply used slacked lime instead (in the form of limewater). I made my own limewater using garden lime.

To start, the Brazil is red because I added some roche alum so the solution is acidic (pH = 4). Once I added limewater, it shifted the pH to alkaline and the color went to purple. I cheated, and nudged it a bit further using a couple flakes of potassium hydroxide since the dye was so acidic to start. With this recipe, it's best to start with a plain Brazilwood extract, so that you don't have to add too much lime to shift the pH.

I brushed on 5 coats of dye to get this color.

[Harry Marinakis]

It's been very interesting to work through these recipes, and to learn the meaning of the funny language. The more you learn, the easier it gets to understand what is being said. For instance, "...give it the first hand of color written..." had me baffled for a while, but then it made sense the more I played around with the process of dye-making.

I am also learning a lot of unsaid nuances of dye making. For instance, a lot of recipes direct you to allow the leather to dry between applications of dye. Now I understand - if you brush dye onto wet leather then very little dye soaks in. But if you allow the leather to dry, then you can brush on a whole lot of dye.

I've got 2 other Brazil extracts in the works (Plictho recipes #17 and #18), one of which should be available tomorrow. The other one has some boiled grain added to it, and it has to ferment for 3 weeks.

There are about 50 leather dye recipes in the Plictho, and I am going to hit most of them over the next 6 months. Stand by.

[CTrumbore]

Follow up on the Padauk dye, after the leather sat out on the back porch for 2 days.

The top half of the image is the backside of the leather that was not exposed to the sun. The original color was more of a salmon than a true red.

The bottom half of the image is the sun-exposed side of the leather.

I bought this BEAUTIFUL orange padauk board on a whim to make something. A year or three later, I was tearing my shop apart trying to find it, and couldnt. I did have this chunk of heavy mahogany I did not recall having though...

[Harry Marinakis]

Plictho recipe #18

This is another brazil dye made from Brazilwood, and it is some good sh#t.

"Measure very strong white vinegar, and put into a phial, roche alum as much as two walnuts, well minced and put into this vinegar and stir often for some days. Then later you will take a glazed pot and put in the vinegar and put again half an ounce of gum Arabic. Take some brazil scraped with the glass and put it into this pot and make it boil until it drops by a third part and a bit more. Strain it with a cloth and save it in a glazed dish. Leave it to rest some days and then use it to your pleasure and it will be very perfect.”

The quantity of roche alum ("as much as two walnuts") comes out to be about 70 grams
Half an ounce of gum Arabic = 20 grams. The gum Arabic gives the dye a pleasurable texture, not too watery.

The amount of Brazilwood and vinegar were not specified. So from my knowledge of other recipes I used 20 grams of brazilwood shavings, covered with 200 ml of vinegar (10 ml/gm). This seemed about right. I soaked the dye bath for 3 days, then boiled, reduced it, strained out the Brazilwood grounds, and reduced it some more to 120 ml.

This gave me a proxy dye concentration of 20 grams Brazilwood / 120 ml extract solution = 0.17 gm/ml

This turned out to be great, although next time I'll shoot for 0.25 gm/ml.

I brushed the dye directly onto virgin veg-tan leather - no mordant. It is very perfect, and this was only 3 coats of dye.

[Mac]

I made a Brazilwood leather dye, using recipe #16 from the Plictho (AD 1540):



Brazilwood 1 ounce = 40 grams
Water 1 pound = 477 ml (12 ml per gram of Brazilwood)
Fish glue half ounce = 20 grams
Roche alum 2 ounces = 80 grams


But I really don't like this recipe - there is so much roche alum in the dye that when it dries the leather sparkles from all the roche alum crystals, like it's covered in glitter.

I did not see this one when you posted it.

There may be an issue with fish glue if the recipe presumes that your glue is dry flakes rather than the modern liquid. There are two possible problems here. The first is about the difference in density between dry and liquid glue throwing off the proportion. The other is about what ever they put in the glue to keep it liquid. If I recall correctly, liquid hide glue contains urea to keep it liquid. This may be true of liquid fish glue as well.

Mac

[Harry Marinakis]

The main issue with that recipe was too much Roche alum. Not only does it sparkle, but it seems that so much alum impedes due uptake as well.

I repeated Plichto recipe #165 with the perfect Brazil (#18) and got the same crappy results as I did with the fish glue Brazil.

[Harry Marinakis]

I was actually able to dye leather a yellow using Old Fustic (Argentine Osage Orange), using roche alum as the mordant @ 15% WOL. I am going to try it again using a more concentrated dye to see if I can get a brighter yellow.

The mordants tin and Roman vitriol were useless, no color at all.

I got an olive color by adding a 1 ml. of vinagroon to the Old Fustic dye. It came out too dark, so 1/4 ml would have been better.

[Harry Marinakis]

Just for fun, here are some of the natural leather dyes that I've been able to create so far.

About half of the colors are from medieval dye recipes; the other half of the colors are from pure extracts.

I haven't even begun to explore the blue, green and brown dyes yet, and I'm only one-third of the way through the reds.

[AwP]

You guys talking about vinagaroon are not getting the results I used to get. One, make sure enough iron is dissolved to kill the vinegar (no more will dissolve). Two, just dip it in, no days long soaks needed. Three, (this is the part I am not seeing in anyone's description) dry the leather with HEAT (remember this is a chemical reaction, not a real "dye") not enough to harden it, but enough to dry it rapidly, I used to just wave it about 6" over the stove burner, not keeping any spot over the flames for very long. Hope it works better for you.

[Harry Marinakis]

I agree, once you get good vinagroon it dyes very quickly, without soaking. The key is to let the vinagroon "mature" for several weeks.

All of the ancient dye recipes from the Plichto and Segreti are very consistent about one thing - that you let the leather dry out of the sun. I think it keeps the leather soft.

[Peter Baker]

This is amazing. I've been dabbling in leather for about 4 years now and over the last year I was considering trying to make my own dyes if I had the time to experiment because I couldn't find much in the way of concise experimentation by anyone else, and this colossal effort has answered almost every question I had about fairly basic coloring.
Not gonna lie, I would have your babies at this particular moment. Thank you so very much for your dedication and time spent explaining.

[Peter Baker]

I can actually help a little, I can confirm that dry leather takes dyes much better than even slightly moist leather, even for modern dyes (the exception seeming to be spirit based dyes). I figured that out tangentially while practicing tooling, and confirmed by trying equal coats applied rapidly versus a day apart and cutting the piece to measure penetration. Waiting for the leather to dry and then wiping the surface with a dry rag to remove loose pigment between coats definitely yielded better penetration and colorfastness.

As for sun drying, my experience both with water based dye and tooling taught me that a slower drying time does keep the leather more supple, without much difference in the stability and longevity of the tooling.

[CTrumbore]

I agree, once you get good vinagroon it dyes very quickly, without soaking. The key is to let the vinagroon "mature" for several weeks.

All of the ancient dye recipes from the Plichto and Segreti are very consistent about one thing - that you let the leather dry out of the sun. I think it keeps the leather soft.

It's due to how it dries. Even release of humidity from the center out, vs sudden release and "baking" from the very surface, while the inside remains wetter, which effectively does a wet/dry/wet/dry cycle to the surface layer, which hardens it.

[Harry Marinakis]

Here is a brown dye made from green walnuts.

You take fresh walnuts, while they're still green (before a nut has formed), and crush them up, and extract the colorant by boiling. The green walnut juice is clear, but upon exposure to air it turns dark brown and stains everything (fingers included).

You can buy green California walnuts in April, May, or June, or you can wait until August/September and collect them locally. The first photo shows 2 pounds of green walnuts.

Hit them with a hammer to break them open, then tear them into little pieces and boil them for a couple of hours. Strain out the walnut grounds and reduce the volume of the dye bath to 1 ml for every gram of fresh green walnuts that you started with. Soak the leather in the dye. A mordant is not required. You can darken the brown further by adding a tiny amount of vinagroon.

[Harry Marinakis]

The leather that you use makes a difference; as stated before by someone, modern vegetable tanning is not the same now as it was in the medieval times, and modern "vegetable" tanning processes may use other chemicals. The dark brown color obtained above was from a 1-hour soak in walnut dye.

I soaked another leather in the same walnut dye for 24 HOURS and got very little dye penetration. The image below shows undyed leather on the left, and the dyed leather on the right after a 24-hour soak. Compare with the brown that I obtained in the post above. Different leather, different results.

Moral of the story: if you want to use natural leather dyes, start with a quality, natural oak-tanned leather.

[Harry Marinakis]

Here is a golden yellow leather dye made from Old Fustic (Argentine Osage Orange).

I decided to repeat the dye test for Old Fustic, using roche alum as the mordant. (See my post above from June 19, 2017.)

Here is the result that I obtained.

The only difference between this dye and my previous dye is that this is "burnt" Old Fustic, sort of like Burnt Sienna. I reduced the Old Fustic extract down to a thick syrup and let it get "burnt" slightly before adding more water. This leather was soaked in dye for 2 days, and the dye concentration was 0.5 gm/ml (125 grams of Old Fustic wood shavings were used to make 250 ml of dye).

The "burnt" dye gave me a nice golden color. I will try this experiment again, to see if I can get a brighter yellow, but next time I will be more vigilant and won't let the dye bath burn.

There are no leather dye recipes in the old manuscripts for Old Fustic, although it was a well-known dye for fiber. There are, however, recipes for yellow leather dyes using turmeric, which I will be exploring at a later date.

[Harry Marinakis]

It's due to how it dries. Even release of humidity from the center out, vs sudden release and "baking" from the very surface, while the inside remains wetter, which effectively does a wet/dry/wet/dry cycle to the surface layer, which hardens it.

Agreed

[Harry Marinakis]

I did some more dye tests with the blue dye indigo, using a couple of recipes in the Plictho.

These are some crazy recipes. Due to the nature of indigo dye, I didn't think that these recipes would work -- and they certainly don't.

Indigo is a rather complciated dye. The water-soluble colorant indican is extracted from the leaves of the indigo plant, and then indican is oxidized in fermentation vats to a water-insoluble compound called indigo blue. This precipitates out of solution, is collected, dried, and sold as cakes or powder.

In order to dye anything, you buy the indigo blue cake and ferment it again with agents like urine, ammonia, lye, etc. to reduce it to a water-soluble dye called indigo white. THIS is what you dye things with; when a dyed item is hung out to dry, the indigo white oxidizes in air back into indigo blue, which is permanent, wash fast, sun fast, and rub fast.

But the recipes in the Plictho and Segreti don't use indigo white -- they just use the indigo blue cake, which you paint onto the leather. Predictably, this doesn't dye anything. All you're doing is applying an insoluble paste to the surface of the leather, which then rubs off on everything.

If anyone knows that I am doing something wrong here, please let me know. Indigo blue is sold as a cake or powder. Indigo white is in a fermentation vat, it's not a powder or anything you can grind up. So I'm pretty sure that theses recipes are using the indigo blue cake and not something else.

I am going to start my own indigo urine fermentation vat and try dyeing leather in the traditional manner, with indigo white.

[Harry Marinakis]

Plictho recipe #179

"Measure indigo one ounce and whiting one quarter ounce. Crush each thing together and make it a paste. Then add to it a little honey and incorporate and extend the said things with hot water. Give it to your skins with the bristle or the brush and it becomes a very beautiful azure. If it is too little give it one hand and give it two hands."

Initially, when you apply the "dye" to the leather, it's a pretty cool steely blue.

But the "dye" is just a paste on the surface of the leather that wipes off easily. I tried to seal the leather with wax and oil, but the "dye" just wipes off and you're left with shit.

[Harry Marinakis]

Plictho recipe #188

"Measure eight pounces of very strong lye, eight ounces of live white lime, sixteen ounces of clear fountain water, a spoonful of olive oil, one ounce of white of egg so that it all makes a bucket of stuff. Put these things on the fire and make them warm up. When they are tepid take three quarti of fine indigo, of Baghdad, and grind it well in the manner of brasilio, and see that it be well in powder. When you have given it one boil take it from the fire, and stir it with a stick, and then put on the cover. Do not allow it to breathe and let it stay thus and save it. When you want to use it make it boil six hours, and should it boil twelve hours it would be better. With this water you can dye any skin that is dressed for dyeing. Nail your skin and dye it in that water. Then take fine indigo, finely ground, and dust it with a cloth over the skin to which you have given one or two hands of that said dye. Then run over all your skins so that they are well colored evenly in the manners observed. With a little common oil go rubbing your skins. Again wet your cloth in the water above said and rub, and then wet with that water the said skin. Allow your skins to dry and if it is not well colored, remove away the color so that it is perfect."

This was a lot of work for nothing. Again, they came out pretty cool when first applied and oiled, but when it dried it rubbed off easily. WTF????????

[Harry Marinakis]

Here is a fine fugitive yellow leather dye made from turmeric root (curcuma) and roche alum. In fact, it's the only yellow leather dye recipe in the Pilctho or Segreti. The dye is applied to the leather with a brush. Turmeric is available as a powder in the spice section of your local grocery store.

Plictho recipe #207 - “You will take a skin that is dressed by the leaf. For each skin take one and a quarter ounces of curcuma that is pestled and two ounces of roche alum. Set to cook in two half mezzette of clear water and make it boil so much that it drops by one third. After having done this, spread out your skins and give them of this color, one hand. Set it to cool and then dry. When it is dried, give it one more hand and do thus until it gets the color that you like. Having done this, give it the strop, the pole, the button of glass and you will have a fine color.”

"You will take a skin that is dressed by the leaf" - that is, use vegetable-tanned leather (oak leaf)

The quantities specified in this recipe work out to the following when converted to modern equivalents:
Turmeric 1¼ ounces = 50 grams
Roche alum 2 ounces = 80 grams
Water two half mezzette = 1,300 ml (26 ml of water per gram of turmeric)

"...give them of this color, one hand..." - that is, brush on one application of dye

"...give it one more hand..." - that is, brush on a second application of dye

"Having done this, give it the strop, the pole, the button of glass..." - that is, soften and burnish the leather

[Harry Marinakis]

FYI
Indigo cleans up with ammonia window spray
Turmeric cleans up with rubbing alcohol

[Harry Marinakis]

Well, I'm finally onto something here with indigo leather dyes.

This is Plictho recipe #191 for dyeing leather a blue, azure, or grey color. The indigo is dissolved in vinegar, lye, or white wine. Adding whiting lightens the color a bit.

“191. Take your skin and fix it on a table and see that the skin is wet and well purged of the dressing. Take fine indigo, half ounce per skin, and that it is ground with some whiting. Then put it into white vinegar, or in lye, or in white wine, and that there be as much gum arabic as in a small nut. See that this mixture is one pound of stuff because so much goes for each two skins. Give it the color that seems to you best, either light or dark.

Should you want to make it blue, add some whiting as said at the beginning of the recipe, more or less according to how you want to do the work. Note that one must grind the whiting with the indigo. Who ever wants it deep azure, do not put whiting, and keep this order. Note that I remind you that to dress a skin of wild roebuck you need two ounces of alum, and twelve eggs and if it is large fifteen eggs. If it is a deer it needs one pound of alum and twenty eggs, and similarly for a nanny goat, more or less. The alum is roche alum.

Also for grey skins, measure roche alum three ounces, common salt one ounce, and thus is done to the medium skins which means skins of heifer.”

This recipe works -- IF you use vinegar instead of lye, and IF you don't use salt in the mordant. The vinegar seems to dissolve the indigo better than water or lye.

Also, if you let the particulates settle and just use the liquid dye, then the color really soaks into the leather and very little rubs off. This dye was much more dilute that recipes #179 and #188; that is, 0.04 gm/ml versus 0.13 gm/ml. I think this, too, helps to avoid smearing paste on the leather.

I tried the recipe for grey, but all I got was a dark brown. The lye-based dye also doesn't work.

I guess that this is the medieval definition of a blue color (from the second paragraph). I call it a slate blue.

It is possible to get a lighter shade of blue, but my leather was streaky after the first brushing, so I applied a couple more layers of dye. If you dipped the leather once then you could avoid streaking, and you would get a much lighter shade of this slate blue - almost a bluish grey.

[Harry Marinakis]

Okay, that's all I'm gonna post on this subject. I'm gonna write a damn book.

[robstout]

Sounds like you are close to it. This has been fascinating.