At Pergamena, we often receive questions from people curious about many different aspects of our business — parchments, leathers, vellums, vegetable tanning, bookbinding, animal skins, goatskins, sheepskins, ostrich skins, calfskins, buckskins, deerskins, red rot, Mike Rowe, Dirty Jobs, workshops, commissions, designs, frames, colors, types, paying a visit to our facilities in Montgomery, N.Y. — so we figured we’d get all of our answers together in one place. If you don’t find what you’re looking for, feel free to send your question to firstname.lastname@example.org and we’ll get back to you as soon as we can.
What is the difference between parchment, vellum, and leather?
As far as parchment and vellum go, the difference is pretty much semantic at this point in history. The roots of the words come from different sources. Parchment arrived in the English language from the German Perkament, which in turn came from Pergamena in Italian (and before that, Pergamena in Latin). We can reach back even further to the word Pergamon, from antiquity, which referred to the city in Asia Minor where the material was first recorded as being mass produced. These days, parchment in general refers to any type of animal skin turned into a paper-like material from physical action, including the removal of extraneous flesh, fat, and hair.
Meanwhile, vellum comes from the Old French word Velin, which means calfskin. Historically speaking, calfskin has been the finest parchment available, so people have long referred to refined parchment as vellum. Here’s a simple formula: All vellum is parchment, but not all parchment is vellum.
Leather refers to the same raw material — animal skin — that has been chemically altered to render it impervious to rot. There are many ways to tan a skin, and the resultant leather will vary in characteristics, but it will always stand up to moisture, heat, and mechanical action better than any untanned/raw skin.
How long does it take to make parchment and leather?
Over the past millennium, the process of making parchment and leather shrunk months to a week or less. We have modern chemicals to thank for this much swifter production period. The process has gone from taking months to now being able to be done in a week or less. On the whole, though, leather still takes much longer, owing to the time necessary to get chemicals and tanning substances to penetrate all the way through a skin.
How do you bind a book with parchment?
If it’s thick enough to remain rigid, parchment can be used as the cover of a book on its own. In this case, the parchment would be sewn onto the text block (the body) and would be considered a limp vellum binding. Parchment can also be attached to boards and then bound onto a text block. This would be a vellum-over-boards binding.
What causes red rot disintegration in vegetable-tanned leathers?
Red rot results from sulfur dioxide in air pollution combining with tanning agents in certain types of leathers. This creates sulfuric acid in the leather, which in turn lowers the pH level and causes the leather to disintegrate. This often leads to the need for conservation of many books.
How should I store my parchment?
Parchment is not meant to stay flat. It was once wrapped around an animal and it is only through tremendous stretching and drying of the skin under tension that it reorients the skin fibers into a very thin but very dense skin fiber lattice. Too much environmental moisture and humidity will cause the fiber network to start to loosen and expand, ultimately warping the parchment until it won't lie flat. Likewise, too dry an environment will cause it to shrink and become stiffer. When the parchment warps, the entire surface is likely to move in several directions at once. We've found the best way to store parchment to keep problems to a minimum is to store it in a stable @ 55% humidity environment, and to keep it gently rolled up head to tail (along the spine direction of the skin). This will obviously cause it to curl, but the curl will at least be predictable in that it will only be in one direction. When you are about to use the parchment, gently roll it in the opposite direction for a day or so.
How do I make my own stretching frames?
We get this question a lot from people who are hunters, DIYers, or artists, among others, who want to stretch their own skins. We developed them just by trial and error but it is a fairly simple design and most (but not all) of the parts are easily available locally:
- Four 8' 4" x 4" beams for the body of the frame, but you can make the frame as large or small as is comfortable
- 8 6" x 1/4" lag screws
- A 1-1/8" spade drill bit
- A 7/8" spade drill bit
- 40 Clothesline Tighteners ex: here.
- 40 Leather spring loaded toggle clips ex: here.
- Several yards of nylon 1/4" cord rope
Our frames are roughly 6' tall x 5' wide inside. This gives us an area about the shape of a skin that we can handle. Cut the top and bottom 8' 4" x 4" rails to a length of 5'. The side pieces will remain 8' and the top and bottom 5' rails are set in @ 1' from top and bottom. This allows for the frame to be stood against a wall with a foot of clearance on the top and bottom. Drill out and screw in the lag screws to attach the bottom and side rails together, 2 per joint for a total of 8. Drill out the outside of the side and bottom rails with the 1-1/8" spade bit to a depth of 1-1/2" at intervals of 5" on center around the frame. Drill out the remainder of the distance through the rails using the 7/8" spade bit. Feed the ropes through the line tighteners, seat them in the drilled out holes, then tie on the toggles and the frame is ready to go. This design can obviously be adapted to fit the size of the hides being worked on. We're happy to share the design and would like to hear if anyone builds them and how they work.
How can I polish leather?
Leather can be polished many different ways, depending on the type of leather. The fact that ours is a vegetable tanned leather with a smooth grain allows for a lot of surface manipulation, either by burnishing and applying heat and pressure, or by applying a polish of some kind. A search online shows that there are almost too many leather polishes out there to mention... Just make sure you use the right type of polish on the right type of leather. The wrong polish on a piece of leather can ruin it! Check out our forum for more tips on polish resources.
When does Pergamena do workshops?
We normally hold them in mid-spring when the weather has had the chance to warm up a little. We take names on a rolling basis and typically try to top off each workshop around 13 people. If you’re interested, please email us and we’ll contact you when we have a large enough group together to organize a workshop.
Can I request parchments or leathers in special colors or types?
We do provide an extensive range of custom colors and leather types. Contact us at email@example.com to let us know what you’re looking for and we’d be happy to produce or source it for you.
Can people come visit your facility/studio?
Without a doubt. Pergamena is open to the public and we’re happy to show visitors around during our weekday work hours. Advance notice does help us carve out some time, though, so please contact us ahead of time if you’d like to arrange a visit.
Do you sell suede?
The short answer is yes. Suede is actually the flesh side of a piece of leather. The other side is called the grain, which is smooth and often glossy. Suede that’s still attached to the grain is called reversible suede. It’s more durable because the grain is holding the flesh together. When you buy our leather, you can use whichever side you prefer. It is also possible to abrade the grain side in a similar fashion to suede. This is often called "nubuck." We are able to custom make either type of this leather, so contact us with requests.
What is pyrogallol?
Pyrogallol is a term used to describe a type of vegetable tanning agent. It has a high percentage of “non-tans,” or non-reactive substances that help to fill the leather. The more non-tans, the less tannins there are available to react with air pollutants, such as sulfur dioxide, and the more resistant the leather is to degradation. It is a slow process, but it is more stable over time than fast-acting catechol tanning agents (the alternative vegetable tanning agents) which are susceptible to red rot. Pyrogallol materials are often harvested from trees such as chestnut, oak, sumac, myrabolan, and tara, among others.