Most artwork you see today will be dust in 500 years, but the Mona Lisa will live on, why is this? (🧵)
In the 1700s if you got a book it would be printed using ink and paper. That paper production would be pretty primitive, but not too chemically volatile. This means that over time the work is chemically stable and tends not to deteriorate too much.
Nowadays, because of modern mass production, if you buy a book it is likely printed on paper with lots of nasty acids and volatile chemicals, that in the span of around 20 - 100 years, will degrade the paper to being almost unreadable.
It used to be that artists would mix paints using gum arabic or egg tempura, and a raw pigment (a substance from the earth that provides colour). Pigments themselves are mostly stable, and gum arabic and egg tempura are both reasonably chemically stable themselves
These days, manufacturers use lots of different fancy chemicals in addition to the pigment. These can result in very volatile chemical mixes, and because of that volatility, some paints made today can only withstand full exposure to sunlight for 3 hours(!) before fading
Different pigments themselves have different light-fastness, which is a measure of how long it takes it to vanish under UV light. If you look at old paintings, sometimes you will see grey or missing colours. This is because the paint literally faded from the page.
In this painting by Jacob Van Es from 1630, you can see not only how the paints have faded over the last 400 years, but also the accumulated grime over the background. Notice the grapes look kinda uniformly yellowy along with the plums and pears, but the strawberries are vibrant.
It's possible that those blackberries were perhaps bluer at one point, or much more vivid and bright. That those grapes were a vivid bright green. But the yellows and reds are the least lightfast colours in the painting, so they have stayed strong these 400 years!
Funnily enough, the page I took that painting from had a critique about inferring the emotional intention behind those colours (e.g. "maybe the yellows represent-") but IMHO it's pretty useless to intellectually analyse a painting that is missing half of it's colours!
And NONE of this mentions digital art b/cos it has a lifetime of around 50 years at most. SSDs have proprietary firmware that writes the bits to the medium in an unknown order. Platter drives keep magnetism for about 10 - 20 years at most. Image formats specs are lost. etc.
Perhaps the best known "longterm" recording medium today is Archival Vellum -- that is, animal skin, prepared in a way that removes acids from it. The best archival vellum parchment can last 1000 years at *least*, assuming it's kept dry and free from moisture.
This is actually one of the reasons why, since the 1800s articles of British Law have been printed on Archival Vellum and stored in a vault somewhere.
The Magna Carta, signed 800 years ago, is still readable. The book you just bought off Amazon won't be in about 50 years.
In summary, the best thing you can do if you want something to last 1000+ years? You put it on Vellum, via a LaserJet printer, and then shove it in a hermetically sealed metallic vault (to avoid moisture deteriorating the parchment) and bury it deep.
The SECOND best thing you can do is to use non-lightfast pigments, and use archival vellum or a long lasting acid-free paper. Most good paint manufacturers will give pigment numbers for their paints so you can look up the chemicals/minerals used for each colour
@alexandria I'm sorry, but you mixed up the meaning of "lightfast". Pigments that are not lightfast fade quickly, and pigments that are lightfast last a long time. (It's the older meaning of "fast" you also find in "hold fast".)
@alexandria sadly there are few things actinic light won’t absolutely destroy given time, so UV-blocking glass is also part of the equation!
@alexandria on the topic of how to make information last, some folks developed a laser etched metal process for this and they offer to etch gold plated tablets.
Needs at least a microscope to read though...
@alexandria pigments also need to have good oxidation properties, which is one of the things that makes organic iron compounds like Prussian blue and iron gall ink so eternal as long as they’re stored well
I mostly know about photographic processes, the modern way to do archival is pigment inkjet (because dyes fade and laser isn’t high enough quality) on high quality paper for color, and for black and white simply toning a silver-gelatin print to convert the silver to more stable compounds.
@alexandria Or you can carve in stone which will last 1000+ years. If that's what you want ...
The best papers to use are cotton rag papers which are naturally acid free. There are also bamboo and Japanese papers which are very fine and naturally acid free.
Wood based papers (in the west) will be treated to make them acid free and are not as good a quality as cotton rag.
@alexandria But you didn't explain why the Mona Lisa has lasted so long.
The Mono Lisa was painted using oil paints on a wooden panel. So vellum and paper are not relevant there.
Also the Mono Lisa has clearly darkened due to the resins used in the paint mix. And extensive cleaning has removed her eyebrows. I think the painting is far too valuable that the Louvre would risk any further restoration to brighten the image - if it can be brightened.
@alexandria There are other formats which also preserve well.
Interestingly, when I saw a copy of the Magna Carta it was displayed along with a Roman stone mosaic which had been unearthed in Israel. The pattern here was formed from the natural colours of the stones themselves, which are remarkably inert. In looking at ancient art it's rare that we can be assured we're seeing colours as they originally existed. In the case of mosaics, what you see is what the artist originally created.
Stone carving and clay tablets (particularly those in envelopes) can of course last millennia, if preserved from weather. Cemetary tombstones may be obscured in a century or less under rain and moss or lichen.
@alexandria there is also the MDisc format for digital stuff.
It's like a DVD/Bluray but with "glassy carbon" as data layer which is supposed to be inert to oxidation.
Those have a projected lifespan of over 600 years if kept dry and between 0-60°C and are marketed with "up to 1000 years" durability.
The question is how long the accompanying drive lasts and/or if we continue to manufacture Bluray drives in the future.
@alexandria oh and that laser burning bubbles into glass thing that GitHub used for their arctic vault project.
Although that's not commercially available afaik
@alexandria AFAIU laserprint is not technically ink but a pigment. That is, it isn't absorbed into the fibres, but is melted onto the paper.
This means that laserprint type is subject to mechanical degredation --- physical handling of sheets, or vibration or other movement within a document might knock loose the pigmentation.
An ink or dye is absorbed into the medium it is applied to, a pigment rests on the surface. A classic example of the latter is Greek statues. Those weren't originally the austere white we've come to know, but gaudily painted with bright pigments which have faded and worn off (as they weren't absorbed into the marble) over the centuries.
Depending on formulation, inkjet (with archival ink) on rag-content acid-free paper might be more durable than laserprint. Both should last centuries under normal circumstances though.
@dredmorbius Yes and no. *Some* laser printers have a carbon toner that is electrostatically held to the page. I have no idea about colour laser printers lol. Pigment based inkjet, does have an assurance but has less of an absolute guarantee imho
@penny Absolutely. The quality of the paper is so much worse and most paper these days have so many more volatile chemicals placed into them during production. I did a quick check and it takes modern paper about 2 weeks to decompose in a landfill 😬
Library conditions are kept dryer and the like but there are a lot of acids and binders and fillers used nowadays that will absolutely ruin a book over time. Slowly the acid will degrade the paper until it crumbles away. Not to mention the fragile and cheap inks used in most paperbacks, etc.
I think it would be interesting getting a book produced in the 1940s or the 1970s and a book produced in the last 10 years and doing a lightfast test of it though
@penny Yeah like, most of these timescales are dealing in like really long periods. I think it should be ~mostly fine~ for practical purposes, acids are pretty gradual although it's surprising how fast they can degrade the quality of the paper (if you compare like, a book freshly bought 10 years ago to how it looks today, there's a visible difference in the feeling and quality of the paper) but probably don't expect for it to be readable for the next generation or their kids basically
Nicholson Baker points this out in his book Double Fold, in which he argues against de-accessioning big collections of broadsheet newspapers because, even though they were printed on cheap paper with awful archival qualities in priciple, because they were bound into volumes, this kept light and air away and so in practice lasted very well.
@waweic @penny Depends on existing light exposure but it's a comparative degradation you'd be after anyway really. Sounds like a cool idea tbh! Might be difficult to do "properly" in a way that other people can use, but sounds cool regardless.
I'd look up other lightfast tests first just to get an idea of what it entails !!
@alexandria damn! that's about when i'll get around to reading most of the books i've bought recently too...
Do you mean to say that *all* modern books are unreadable so fast, or is there still paper that lasts longer?
@alexandria I doubt the 50 years number. I have plenty of books printed in the 60s and 70s. All of them are perfectly readable, although the paper is getting a light brown tan due to acid in the paper.
Ever since the late 80s, printers have been switching to acid free paper and today all paper is acid free (mostly because it's cheaper). So, I expect the books bought today, last a leastt 100 years, probably longer.
@alexandria I'm not sure that painting has faded all that much. Yellowing and darkening usually happens from varnishes and resins, often mixed into oil paint. Or a build up of dust can darken a painting.
Also that painting has no blackberries in it. And I think the strawberries are actually raspberries. There are two raspberries on the table that are not in the bowl.
Colours can be missing from paintings because of excessive cleaning which removes the top colour. Mono Lisa once had eyebrows.
@alexandria We're also witness to survival bias here. The inks and media which didn't survive the test of time ... haven't reached down to us.
I believe it was Leonardo who'd lost an early version of his Last Supper painting when the wax-based pigments he used melted under the torches he was using to dry the paint...
The work ended up being repainted, though I forget if that was by Leonardo himself or another artist (possibly Michelangelo?).
(I'm remembering all this very hazily from a 1970s / 1980s BBC dramatisation.)
@alexandria A big part of the survival of old paper is that it was based on rags --- cotton and flax fibres mostly --- rather than wood pulp.
Pulp paper is naturally acidic on account of naturally occurring tannins in wood itself, let alone what else is added to it. It's cheap, enough so that falling paper prices and increasing press speeds massively increased printed material availability through the 19th century, but unstable, as you note.
Modern archival-quality paper (acid-free, high cotton content) should be good for 500+ years survival.