Tuesday, 29 October 2013

Green dye experiment (with pictures)

Over the weekend I finally got around to experimenting with ripe buckthorn berries to make a green leather dye. The tip that triggered it was something I found on the Yale Traveling Scriptorum site. They created a small book of the recipes they were using for their project.

In a footnote in the booklet they referenced how they prepared their buckthorn berries since they bought them dried rather than fresh (from the same supplier where I bought mine). So, that solved question one I had about how to reconstitute the berries in a useful way. I figured soaking them in water would work, and had played with that a bit when the supplies first came in, but it was good to confirm it worked from a secondary source.

The recipe I'm using is in the Plictho and is the one I've been laughing about since I first got the book. It uses paternosters as a measurement of time (as in boil the mixture for the time it takes to say six paternosters). Now, I have no idea how long that is, but based on the length of text and normal speaking rhythms, I've guesstimated that it takes 1-2 minutes to say a paternoster. So, I boiled my mixture for 10 minutes.

I've done two samples, one with the leather untreated (other than using a deglazer to remove any surface finishes and dirt) and one pre-soaked in my alum water. I want to see how much of a difference it makes.

To make the dye I basically soaked some berries in tap water overnight to re-hydrate them. I then put them in a pot with a bit of alum, covered them with vinegar and boiled them for 10 minutes. I included the water I was soaking them in on the theory that there would have been juice in the berries if they were fresh. It may have weakened the vinegar a bit but I'm using strong vinegar (10% acid as opposed to normal white vinegar that is about 5%) so it should still be OK.

Once it had boiled I poured it into a jar and let it cool. It's a really dark, mucky colour. It almost looks black or dark brown in the jar, but when you paint it on the leather it's a bit like a dark olive colour. Interestingly, when you rinse the brushes, it comes off in the water as a yellowish colour (which makes sense since unripened buckthorn was used in period for yellows).

I applied two coats of colour on both sides of the leather and let it dry. Both pieces turned out a yellowish colour with a hint of green,

Applying a coat of olive oil  darkened both pieces a bit. They definitely have a green tinge to them, but are in the yellow/brown tones.

Here are the pictures:
This is the colour before I add the olive oil finish. Much yellower.

This is the colour after the oil layer. The piece on the right is the alum treated leather, the piece on the left is the untreated leather.  Underneath is the yellow dye that I did in my first experiment as a comparison.


The alum treated leather was much stiffer but otherwise I didn't notice much difference in colour or colourfastness. The green isn't quite what I was looking for, but it's pretty similar to what the Yale scriptorium achieved. I do have another recipe that includes verdigris, which might make a more blueish colour.

Tuesday, 22 October 2013

The Ælfwyn Effect - Pics of my red leather dye

Here are pictures to show where I landed with my red dye. As mentioned in my previous post, I was chatting with Mistress Ælfwyn  and she suggested that I apply some oil to finish the leather to see if it would bring the red back out.

As you can see, the red is nowhere near as rich as before it dried in the first picture (its more a terracotta than a true red, but its much darker than when it dried our). The colours are a bit off since this is indoor light and a flash on my camera but you can see the difference in the bottom picture. Before I applied the oil, the piece on the bottom right was the same as the piece on the bottom left.

I'd say it's progress, although the colour is still not as red as other examples I've seen from Karl Robinson (http://www.karlrobinson.co.uk/leather_dyeing.php) and Yale (http://travelingscriptorium.files.wordpress.com/2012/08/dyed-leather-parchment.jpg).

Picture before the dye dried fully
Picture after it dried fully and then an oil coating was applied

The joys of translating period recipe ingredients

In reading my various leather dye recipes (and the same thing happens when looking at cooking recipes too), I keep seeing strange ingredients that I've never heard of before. This presents a challenge as you have to figure out what it could be.

In my earlier recipes, I had to figure out what curcuma was. Turns out is plain old turmeric. Not so hard really with a bit of Google-fu.

But sometimes the period names are really rather intimidating.

Case in point, a number of my recipes call for something called "Roman vitriol". Now, I don't know about you, but to me that sounds like some pretty nasty stuff. Probably not something you'd want to keep in your house, right?

And besides, where the heck are you going to buy "Roman vitriol"? I don't really have a handy store that carries ancient Roman chemicals down the street. Although, come to think of it, I do.

Because you see the scary sounding "Roman vitriol" is modernly known as copper sulphate, which is used to kill roots in septic systems, and sometimes to get rid of algae in ponds. I can actually buy it at Home Depot a couple of blocks from my house.

Now, copper sulphate is still pretty toxic stuff so you have to handle it carefully. But it just doesn't have that scary ring to it that "roman vitriol" does.

Monday, 21 October 2013

General update on this and that.....

I haven't had a huge amount of time lately for any leatherworking projects but a busy period is coming up.

Coming up, we have:

Nov 2: Feast of the Hare, which is our Barony's big event normally, but will be even bigger this year since our new Baron and Baroness will probably be stepping up.

Nov 10: Teaching my leatherworking class at Harrowgate Heath. It had to be rescheduled due to work overtime, so hopefully it will be good to go this time.

Nov 16: Fall A&S, where I'll be entering my leather dye project in the Queen's Prize Tourney. I'm done my first draft of the documentation, and most of my actual work is done (unless I decided to try to pull off more colours between now and then).

Dec 8: Canton A&S competition. Not sure I'll be entering anything since its supposed to be for first attempts and I don't really have anything new I've been working on.

Feb 22: Practicum, may offer to teach my leather class and Avelyn and I have been tossing around the idea of doing a couple of classes on media relations.

Mar 29: Spring Kingdom A&S, where I plan to submit my stick-purse. Depending on how things go at the Fall A&S I may also update my leather dye project and resubmit it.

I did do some minor armour repairs for Avelyn so she could fight at Border Spat this past weekend. Just fixing a broken strap and such, nothing super exciting.

I think one of the bigger items of interest came from a conversation I had over the weekend with Mistress Ælfwyn about my leather dye project. I was telling her about my frustration with the way the red dye faded as it dried, and she suggested I try finishing it with oil anyway, as it might bring the colour back out.

I pulled out some olive oil, which seemed period appropriate given the recipe was from Italy. I know olive oil is often used instead of neatsfoot oil, and is what Karl Robinson uses to finish his period dyed leather (according to his web site).

It definitely brought the red back out, although its more brownish-red than the original colour before it dried. I let it dry overnight and it still kept some good colour, so I'll see what it's like when I get home from work today.

I suspect most of my work over the next few weeks will be on trying to get my leather dye project ready for Fall A&S. Once that's done I'll need to start the construction of my stick-purse so that it will be ready for March.

Once those two big projects are done, I think I'm going to switch back to doing some leather carving. I owe a few people some award badges, and I have to work on the Herald's binder of Harrowgate.

Tuesday, 15 October 2013

Weekend red dye experiment - with picture

Well, it still sort-of works. The picture below shows the work I did this weekend on my red leather dye. It took me all weekend to do three coats of dye because the recipe says to let it dry between.

As you can see, it still didn't really work very well.

The top piece of leather is the natural leather as a comparison for colour.

On the bottom right you have the leather colour when its still not fully dry, which looks pretty good. I did the last coat on that piece before I went to bed, so its been drying about 10 hours.

The piece on the bottom left has been drying since yesterday afternoon, so closer to 18 hours. It's the same number of coats of dye as the other piece and actually looked about that same colour when I went to bed. It still has a slight red tinge to it but not what I would expect.

I suspect by the time I get home both pieces will look about the same.

I'm not sure why all of the colour is vanishing when it dries, I just don't get it.

Wednesday, 9 October 2013

Red dye test sorta, kinda worked... a bit

I got some really strange results from my first attempt at getting the read dye to work. I definitely got some red, but not what I was expecting and not sure how to fix it.

I followed the instructions, or at least my interpretation of the instructions, and got a red liquid with some sediment on the bottom.

I let it cool until it was a bit warm (as per the directions) and then painted both sides of a piece of leather (as per the directions) that I had cleaned with my standard deglazing liquid (basically rubbing alcohol I suspect).

This is where it got strange. The dye just made the leather wet, with no sign of tinting, but as it dried, a bit of a red blotch formed on part of the leather (I think where the leather was in contact with the surface it was resting on.

The blotch is on both sides of the leather, but everywhere else is just the regular tan colour of the leather.

I tried applying more layers the next day but it didn't make any difference (possibly because the mixture had cooled and sat too long?). No matter how many layers I applied after the first one, the only change I got was around the raw cut edges of the leather, where it got a bit of a dark brownish red.

The good news is the red blotch seems to be very much fixed, it doesn't rub off and the liquid didn't seem to affect it, so if I can figure out why the first layer acted the way it did this could work really well.

Tuesday, 8 October 2013

Starting my documentation for period uses of colour on leather items

Colour can be found on many period leather items. There are lots of examples of extant artifacts in museums still showing the original colours, or at least enough traces that indicate they had been coloured originally. We also frequently see examples in artwork of objects that could be made of leather (frequently pouches) that are different colours.

There are really two types of examples, objects that were fully coloured, and objects that have designs painted on them (often in combination with leather tooling).

It's obviously difficult to tell from the artwork whether a coloured object is made of leather or fabric, but there are some ways to make an educated guess in some cases. For example, with the stick-purse the two extant examples with this design both have flaps made of leather (even the Mary Rose artifact where the pouches may have been made of fabric).

The focus of my A&S project is the period dyes, rather than the painted decorations, but I think it's important to understand the different uses of colour in period as part of that discussion.

Painting on Leather:

The Reverend's Big Blog of Leather has an interesting post on the history of leather painting (this is actually the first of a series of posts on the topic as he does some experiments on various techniques).

Another resource, this time on painted shields, was linked to in the previously mentioned blog post. Mostly about painted wood but has a few tidbits related to leather and a lot about period pigments.

Here's an excellent example of painting on leather. The case for the Imperial Crown of the Holy Roman Empire, 14th century The Kunsthistoriches Museum:  http://bilddatenbank.khm.at/viewArtefact?id=100456

My badge carving project, while using modern paints/dyes, would be a similar example.

Dyed leather:

As mentioned in some previous posts, I have four different period dyers manuals that contain recipes for dying leather, which is pretty strong evidence that this was a practice done in period. Given that they are from several regions and time periods, it also suggests it was fairly widely done. Most of these recipes are for dying the whole skin as part of the preparation of the leather. The coloured skin would then be used for making leather items (like pouches, clothing etc.)

To show that these dyes can work, I point to Karl Robinson, a leatherworker and merchant in the UK. He uses period dyes from one of my four sources for his leather items.

I believe there are references in Goubitz's Purses in Pieces of coloured leather, I'll have scan it for mentions of colouring as part of my documentation.

Since the trigger for this project was my stick-purse, I've got some examples from that research that apply here. There are several period paintings of stick-purses with coloured flaps. Based on the extant examples, those flaps are probably made from leather and it's likely the leather for these flaps would have been dyed rather than painted. Here's one artwork example.

The Banker and His Wife, REYMERSWAELE, Marinus van (16th century)

Sunday, 6 October 2013

Dye Updates

Still no luck with the blue dye. I tried another approach this time, making up a solution with alum as a mordant and pre-soaking the leather. That didn't seem to make much of a difference, other than stiffening the leather up. The blue just rubs off with a damp cloth again.

Now I'm starting to wonder if the issue has more to do with the indigo I'm using. All of the instructions I see for fabric dying with indigo calls for all kinds of processes to dissolve the pigment into the liquid. I'm wondering if maybe the "indigo" being used in my recipes is somehow different from the dry powder that I'm getting modernly.

Whatever the case, that's now five attempts using two different recipes, so I think I'm going to move on for now. I`m running low on indigo powder anyway. I`ve ordered more (plus some gallnut extract and lye for other recipes) but may as well work on another colour so my A&S project doesn`t stall.

I've started work on a red dye recipe. First step was to mix a bit of water with some brazilwood dust and let it soak overnight, which is happening now. Tomorrow I'll add some more water and boil it for a while, and add in some gum arabic. Hopefully this one will work better.

As part of the recipe I had another Italian measurement to figure out, this time a quarti.

Just to document what I found, this is what I used:

Quarti = 0.6625 litres

Post period definition of a Quarti is that 1 amphore of wine = 16 quarti = 137 english gallons

Tuesday, 1 October 2013

An inventory of period leather dye pigments

Just like I did with my inventory of colours, I thought it might be helpful to go through my four sources and inventory what ingredients seem to have been used for pigments used in leather dying. It's probably important to keep in mind that what pigment sources were used would have varied by region and time period, so there is a fair bit of variance between the sources.

However, this list at least provides a source for the ingredients that we can show were in fact used (even if not widely) at some point in period for leather dyes.

I haven't done any deep research into the less common of these to figure out exactly what they are (for example, I know about murex and lac but not sure what "murex lac" is). Some of these ingredients (like the murex lac) are used in making compound pigments, rather than as dyes on their own.

I'm pulling this information together as interesting detail for the documentation of my Fall A&S project for the Queen's Prize Tourney, but thought I should post it here as it could be useful for other people as well.

Black grape skins
Curcuma (turmeric)
Grains of Narprum (may be Buckthorn berries)
Gum lac
Kermes (also referred to as vermillion)
Litharge of gold
Lulax (compound pigment)
Murex lac
Privet berries
Raphanitis/Ireos flowers (Iris flowers)
Reno citrino (no idea what this is)
Ripe Buckthorn berries
Verzino (compound pigment)
Walworte (also referred to as elderberries)
White lead