Michelangelo & The Science of Fresco Painting | Chemistry Meets Art

Michelangelo & The Science of Fresco Painting | Chemistry Meets Art

[DIGITAL TONE] What involves volcanic
ash, dangerous chemicals, extreme heat, expert
timing, ground pigment, and expert creativity? You guessed it, Fresco painting. Check this out. [MUSIC PLAYING] NARRATOR: Support
provided by the Glick Fund, a CICF fund focused
on inspiring philanthropy. Additional support provided
by the Christel DeHaan Family Foundation in honor of
the children and families of Christel House. Fresco painting
using wet plaster dates back to 1500 BC and the
Island of Crete in Greece. Of course, fresco can be
seen around Ancient Greece as well, often within
tombs, depicting scenes of everyday life. There are even scenes of a
couple dudes just reclining at a banquet. However, where we really
see some incredible examples is in the ancient
city of Pompeii. In 79 AD, Pompeii was
struck by the eruption of Mount Vesuvius,
which completely buried the city in volcanic ash. To our advantage– definitely
not to the people of Pompeii– much of the city was preserved. Check out these amazing
fresco paintings. Fresco painting was
definitely the wallpaper of the day, so to speak. They included scenes
from everyday life, which told stories of daily
life, including everything from being a vendor to a
competition between Pompeii and a rival town, sort
of a “West Side Story,” Sharks versus Jets thing. Apparently, things
got pretty bloody, which tends to happen when
knives and swords get involved. Fast forward to the
2nd and 3rd century AD in Rome, where fresco
painting makes its way into the wells and vaults of
the underground catacombs, with biblical scenes
on the limestone walls. Fast forward even further
to the 13th century, where we see fresco work exploding. Of course, once painters
like Raphael and Michelangelo got a hold of the style,
it was the go-to technique. Now that you know
the basic history, let’s explore what is
happening within the chemistry, during the process
of fresco painting. Let’s break down
what we are going to need to make this
wet plaster mixture. First is limestone. Limestone is a very
common rock found in shallow, calm,
warm, marine waters. It has a simple
composition consisting of one calcium atom and one
carbon atom and three oxygen atoms. To prepare the
limestone for plaster, we must calcify the
limestone first, which means heating
it to 1500 degrees Fahrenheit or roughly
three times the temperature your oven at home can reach. This process of adding
heat breaks down the calcium carbonate
into calcium oxide and carbon dioxide. Releasing all the CO2 in the air
isn’t exactly environmentally friendly. The calcium oxide we
create from the limestone is called quicklime. This quicklime, which
consists of only one calcium atom and one oxygen atom,
is now a rather toxic powder of refined limestone. In fact, this lime
is now an alkali. An alkali is a basic
ionic salt or earth metal that dissolves in water. Since this quicklime does
have a pH greater than 7, it can cause a chemical
burn on exposed skin. Keep this in mind as you imagine
Michelangelo and his team working daily with
this chemical, 60 feet off the ground. Dangerous? You better believe it. Second ingredient
is water or H2O. What happens next
is fascinating. When we take lime
and add H2O, the two react chemically, creating
tremendous amounts of heat. In fact, tremendous amounts,
as in enough to boil water. Once you add the calcium
oxide or quicklime to water, it is now calcium
hydroxide or slate lime. The third ingredient is sand. Any idea why they
would add sand? You would think it would
absorb the water, right? Not exactly. Sand, which is basically
microscopic particles of shells, fish bones, and
rocks won’t absorb water. But the space created
between these particles can most definitely
hold water and air. Adding sand created space
within the plaster mixture, allowing the necessary
carbon dioxide to creep in and quicken the
creation of calcium carbonate. But you have to be really
careful how much sand and water you add to the plaster mix. At the beginning,
Team Michelangelo was adding too much water, which
wasn’t allowing the plaster to dry quickly enough. This caused mold to
form very quickly. Mold on a painting? Yeah, that’s not so good. Michelangelo, on the other
hand, had an ingenious idea. In order to speed up the
drying time of the plaster and to attain the smoothest
surface to paint on, Michelangelo added ground
volcanic ash instead of sand. This idea had been used
within those ancient Roman catacombs we just talked about. And guess where he
got this ash from? Remember Pompeii? Yep, this volcanic
ash came from Mt. Vesuvius, the same volcanic
ash that destroyed the city. As the slaked lime within
the plaster mixture continues to heat up, it
reacts to the carbon dioxide in the air. Here’s what amazes me. As this carbon dioxide
is reintroduced into the slake lime, the
lime begins to harden and creates these crystals. These crystals are calcium
carbonate, or CaCO3. Does that look familiar? It should. It’s limestone. Yep, you guessed it. We have come full-circle back
to the original molecular structure we started with. We’re back to limestone. Before adding paint,
you would typically need to add two layers of
plaster, called the arriccio. After the arriccio layer dries,
the final intonaco layer, or smooth layer, is added. Of course, Michelangelo and
the other fresco painters had to paint quickly on
this wet plaster layer before it turned
back into limestone. As the paint sinks into the
quickly drying intonaco layer, the pigment is now being
blended into the calcium carbonate or limestone. Now that the pigment is fused
into the limestone layer, it is very stable and can
survive for centuries. I don’t know about
you, but I had no idea just how much science was
involved in fresco painting. Pretty amazing, right? [MUSIC PLAYING] On May 10, 1508, work begins. And man, what a job
Michelangelo has in store. Let me just short-list
some of the crazy issues he will have to face. MAN: Man, that’s really high. One, he has to remove
all the old plaster within the chapel, which
was going to be a huge mess. Two, the chapel was not going
to close while Michelangelo was painting. So normal scaffolding
covering the chapel floor wasn’t going to work. Three, it’s Rome. And it can easily get to
90 degrees in the summer, and that’s just standing
outside on the ground. Four, Michelangelo was
painting in fresco style, which had very little
experience with and is one of the most difficult
forms of painting ever. Five, the height within
the chapel was crazy. The ceiling was over 60
feet above the ground. That’s over six stories tall.

30 thoughts on “Michelangelo & The Science of Fresco Painting | Chemistry Meets Art

  1. With the paint drippings falling into Michelangelo and his apprentice's eyes while laying on their backs to 'cement, wet plaster, lay templates of the drawings and then paint these ceilings would have taken it's toll on the strongest of Michelangelo and his students besides slowly blinding them and crippling them from the laying on the "bridging" or scaffolding that held them to the very top of the ceiling for Hours a Day!!! … as just seeing in the -Michelangelo & The Science of Fresco Painting | Chemistry Meets Art video we just watched.. the Volcanic ash or 'Porcelaina' used in the making of the bonding agent for the fresco would, and also from a personal note, this cement would dry the oils from a persons skin until the cracking and bleeding of the skin would become unbearable…… this I know from my personal involvement in the constructing of the building of the bridgework from 287 over the saw mill as well as the building of the Westchester Airport while in the carpenters union…. This work is tedious and backbreaking… "but this we do in the name of Art.and construction which in my opinion is an extension of Art. Dino

  2. I had no idea frescoes were so complex! I am doing a research project on murals and the website I was using simply said "Mixed with water and pigment on a wet plaster, the paint interacts with air, causing a chemical reaction which fixes the pigment particles in the plaster." I was curious about what exactly this reaction was. Thanks for the detailed video!

  3. Although quicklime was slaked, the dangerous job of producing lime putty is left to others (besides the artist) to mix and age. Artists want well aged lime putty. They only use fresh lime putty if given no other choice. Even so, lime putty is also caustic. More dangerous to the artist are the use of various pigments some of which are toxic. I doubt Michelangelo wore glasses and the “paint” used in fresco is watery and easily dripped. Painting in contorted positions to avoid getting paint in your eyes and to properly see what you are doing takes a toll on the body. The long hours of painting also add up. Buon Fresco is a wonderful medium and one which is thankfully still in use today.

  4. I really enjoy your programs. Forgive me a little pedantry: the woman's head at 1:56 is encaustic, not fresco. Also, intonaco is pronounced in-TON-ak-oh (some Italian words have their emphasis on the third-to-the-last syllable). While I'm at it, Michelangelo was born in Cap-REY-sey, not Cap-Rees (as you pronounced it in your excellent and entertaining biography of the maestro).

  5. Michelangelo complained about working in fresco in one of his most famous poems, which includes a drawling of him standing up painting the Sistine ceiling. He designed a special scaffolding to paint the ceiling because it would have been too complex and required too much material to do it from floor to ceiling. Finally, he was an expert in fresco painting. He was apprenticed to Domenico Ghirlandaio when he was a boy in Florence, and learned the techniques from a true master. He knew exactly what he was doing as a fresco painter, from the drawings, to creating large scale cartoons, to transferring the images, to mixing the colors, etc. He was a master in ALL the arts – painting (fresco and tempera, drawing (black and red chalk, as well as pen and ink), architecture, engineering, POETRY, and, above all, sculpture. It is wrong to say he did not know how to paint frescoes. He did, and was very, very good at it, working in the true buon fresco technique. Leonardo da Vinci is the one who experimented with frescos, mixing oils, buon fresco and secco, often with disastrous results. I have my Ph.D. in art history, and have taught it for many years.

  6. Serious problem at 2:05.
    You refer to the 13th century, and show a work from the early 16th century (that means the early 1500s).
    The 13th century was the 1200s, right?
    There ARE frescoes dating from the 1200s, but they are not very common, and are often badly deteriorated, or have been painted over. In the early 1300s, a famous Italian Master, Giotto, worked in Padua and Florence. He had many students and followers, and many frescoes exist from the 1300s.

    In the 1400s, there were two really important fresco painters from Florence. One of them was Benozzo Gozzoli, and the other one was Domenico Ghirlandaio. Of these two painters, Benozzo Gozzoli is much the more popular because he painted the charming fresco of the Three Kings with the famous image of the young King on a white horse. Look it up.
    Domenico Ghirlandaio is nowhere near as generally popular, but he was a superb craftsman, and his works were exactly what his patrons wanted- they showed the wealthy people of the city taking part, or being witness to religious scenes, like the Birth of John the Baptist, where all the daughters of rich bankers are coming to call on the new mother.

    Part of Ghirlandaio's importance was that he TAUGHT Michelangelo. This means that although Michelangelo was primarily a sculptor, in his teen years he had been meticulously trained in the art of fresco by the most competent master of the 1400s. He COULD paint in fresco, and when the Pope told him to paint the ceiling, the Pope already knew about his background.

    The sentence "Once painters like Raphael and Michelangelo got hold of the style, it was the "go-to" technique."
    This is a REALLY SILLY sentence.
    1. It is mildly annoying to have you put Raphael ahead of Michelangelo in a list of two. Michelangelo was the older painter, and his frescoes in the Sistine Chapel were FAR MORE influential than Raphael's. Raphael was directly influenced by what Michelangelo was doing. Michelangelo was not the tiniest bit influenced by ANYTHING that Raphael chose to do. He locked him out, and tried to pretend that he and his team were not painting the rooms 50 metres away.
    2. This was not something that they "got hold of". This was something that they were both trained to do since they were children. Both had been trained in great big busy workshops with lots of commissions.
    3. Painting fresco did not become more important "the go-to technique" because of the work of these two men. Frescoes had been used in both churches and palaces for centuries. The difference that the Sistine Chapel Ceiling made was that in the following 200 years, a number of churches received elaborately painted ceilings. But the technique of oil painting become widespread in the 1500s, and it was much easier to paint large canvases and set them into frames on the ceiling, than to paint elaborate frescoes.
    4. Along with criticising fuzzy terms like "got hold of" and "go-to", I want to mention the misuse of the word "style".
    This is VERY IMPORTANT for anyone who writes or talks about art to use correctly.
    What is a "style"? A style has nothing to do with the technique (although the technique might affect the style). The two words are not interchangeable.
    Fresco is a METHOD used for painting. The technique for painting fresco might differ from artist to artist, depending on how they lay the plaster, apply the drawing and paint the colour.
    The "style" is the way the painting LOOKS. Michelangelo's STYLE was nothing like Raphael's style. You would never mistake a Raphael fresco, or even a Raphael figure in a fresco for one of Michelangelo's. Not even when Raphael was deliberately trying to COPY the style of a Michelangelo figure, which he did, probably deliberately to annoy Michelangelo.
    Their styles were entirely different.
    Michelangelo's STYLE, specifically, made a huge difference to the history of painting. Not to fresco painting specifically, but to all types of figure painting, mostly in oil paint which was of growing importance.

  7. He didn’t lay on his back. He stood upright with his head tilted back. He had terrible neck problems as a result. He wrote a letter describing his process along with a drawing of himself painting.

  8. Hi! Have you looked at Herculaneum? It was preserved much more than Pompeii. In Herculaneum the furniture was still there…a touch charred but still there. The roofs are still there…and the various levels!
    Anyway, Pompeii has nothing on Herculaneum.

    Just a thought…what do you think Michelangelo would do if he had access to what we have access to in the present?
    God Bless!

  9. This is 2019 and we had a massive understanding of chemicals, how much did they understand of the process? And I wonder how they found our about the mixture. These three videos have been superb, I learnt so much thank you.

  10. Good chemistry lesson, but a bit iffy on the art history.
    My main issue is that fresco (and secco) painting was the dominant painting technique since antiquity. Although the revival of antique art in the renaissance did a great deal to culture, it certainly did not reintroduce this technique as it was highly abundant in the middle ages (Byzantine art in particular). I can see the nitpicking has already been done, but I felt the above was a valid correction to be made, as art history is an extremely complicated field still under research with constant re-evaluation. Chronology is really the least of its worries, still good to point out for the sake of those who dont study it in depth.

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