Death Is One Word For It

Translation is another.

Tincalconite after borax. Photo by me, on display at NHMLA.

Two True Things

I watched it on a screen.

Julie Tolentino’s installation was already weeks into its transformation when we spoke — borax crystals she had grown onto the sculptures, beginning to dry, fracture, and, in her framing, die. That was the intent. Decay as artistic fact. She had designed a system for making something and then watching it come apart, and it was working exactly as she’d planned.

She was right.

What I couldn’t stop seeing was the tincalconite. Na₂B₄O₇·10H₂O shedding water molecules until the structure reorganizes into something else — Na₂B₄O₇·3H₂O, a different mineral, stable under the drier conditions of the gallery. Not a lesser borax. A translation. The transformation she had framed as ending was, crystallographically, a record of the environment writing itself into the material. The sculpture was not dying. It was indexing.

I watched the borax fracturing on screen and thought: she’s going to ask me what I see, and what I see is a birth, not a death. Not a correction of her reading — an addition to it. The borax was dying. That was real. And in the same motion, something that had never existed in that gallery before was forming. Tincalconite. Na₂B₄O₇·3H₂O, stable, new, a mineral record of the exact conditions of this room, this installation, this specific act of letting something go.

I wasn’t sure how she’d receive that. I wasn’t offering a better frame. I was offering a second one.

The borax didn’t have a preference. It just kept changing.

I held both readings at the same time and didn’t know what to do with that, which wasn't a feeling I expected to have while watching crystal chemistry on a laptop. But there it was. The borax died. Something formed in its place. The sculpture kept changing. All three are true. I’m still not sure what to do with that.

I’ve been thinking about that gap ever since. It turns out it isn’t new.

What the Hands Already Knew

The first thing that surprises most people about calligraphy is that the pen is not the point. The paper is.

I do pointed-pen work, which means the nib is split—two tines that flex under pressure and release ink through the gap. Get the paper wrong, and the nib catches on the fibers, and the line explodes. Too loose a fiber structure and the ink bleeds sideways before it can form. Too compressed and it sits on the surface and won’t soak in at all. The ink has to match the paper. The nib has to match both. All three have to arrive at the same moment, or nothing works.

Nobody told me the ratios. I learned them by ruining things.

I spent more than I should on a bottle of ink, watched it feather and bleed across four sheets of Japanese paper I’d bought by the sheet, and only understood what went wrong when I switched to hot-pressed watercolor paper, and it finally held — the ink was never the problem.

What I was learning, without calling it this, was materials behavior. The fiber structure of the paper, the viscosity and surface tension of the ink, the spring constant of the nib — these are not poetic considerations. They are physical properties that interact in ways that cannot be fully predicted from first principles. You have to feel them. And once you’ve felt them enough times, you carry the knowledge in your hands before it reaches your head. The medium doesn’t just carry your intent — it argues back. What you meant to say and what arrives on the page get negotiated by the material itself. Get that wrong, and nothing you meant to say arrives.

Cennino Cennini knew this in 1400. He just knew it about different materials.

While the original Cennino Cennini book has not survived, at least I could not find it; here is another book from that time period, and written in Florence. La sfera by Dati, Gregorio, 1362-1436; Dati, Leonardo, 1408-1472; de Fidelis, Gaspar, scribe.

Il Libro dell’Arte — The Craftsman’s Handbook — is a practical manual for painters working in Florence at the end of the medieval period and the beginning of something else. It is not a scientific document, and that is probably why it survived. It is a record of what happens when you pay close attention to materials for a long time and write down what you notice.

On azurite, Cennini is precise. Grind it too fine, he says, and it loses its color. The blue goes gray. Stop before that happens. What he is describing — without the vocabulary — is the relationship between particle size and light scattering in a crystalline pigment. Coarse azurite particles scatter light differently than fine ones. The color lives in the grain. Grind past a certain threshold, and you have destroyed the optical structure that made it blue in the first place. Cennini knew this. He learned it the way I learned whatever I learned at my desk. By watching it happen.

The painters of that period were working with a mineral palette that required this kind of knowledge for every color they mixed. Azurite — Cu₃(CO₃)₂(OH)₂, monoclinic, sensitive to grinding pressure and to the chemistry of the binding medium. Smalt — cobalt-doped potassium silicate glass, ground to a blue powder — was never as stable as it looked. The blue exists only while cobalt ions sit in tetrahedral coordination within the glass matrix. When potassium leaches out, driven by moisture and the oil medium itself, that geometry shifts to octahedral, and the blue doesn’t fade — it structurally ceases to exist. The dominant wavelength of Rembrandt’s Night Watch smalt has drifted from deep blue toward orange-yellow. Almost none of the original blue survives. Cinnabar — α-HgS, hexagonal, brilliant red, with a tendency under prolonged light exposure to reorganize into β-HgS, cubic metacinnabar, near-black. Vermilion passages in paintings that are now dark brown were once red. The crystal changed phase inside the painting.

Smalt was ground and used as pigment. Rembrandt’s Night Watch used it extensively. Smalt degrades through a complex chemical reaction where potassium leaches out of the glass, causing the vibrant blue paint to permanently lose its color and turn a mottled gray, yellowish-brown, or olive green. The sash around the person on the right image was likely blue originally.

The substitution they didn’t mention:

There is an economic layer to all of this that sharpens the picture considerably. Lapis lazuli — the source of ultramarine, the blue that medieval and Renaissance painters reserved for the Virgin’s robes — was worth more than gold by weight in 15th-century Florence. It came from a single source: the Sar-e-Sang mines in what is now Afghanistan. Every gram of it that arrived in a Florentine workshop had crossed mountains, trade routes, and hands that each took a percentage. Patrons who commissioned religious paintings specified lapis lazuli by name in the contracts. They could verify it by the quality of the blue. They were paying for a critical mineral, and they knew it.

Painters knew this too. So they used azurite — local, cheaper, optically similar enough to satisfy a patron who wasn’t looking closely — in the background passages, the secondary figures, the shadowed folds of the robe where the lapis would be less examined. The substitution is documented in both the contracts and the conservation records. It was an economic decision encoding a precise mineralogical judgment: this pigment will read as close enough in this context, under these conditions, at this viewing distance.

That is materials science conducted under financial pressure in a competitive market. It is also the kind of knowledge that does not survive in written form, because no painter was going to write down the substitution guide. You learned it by working alongside someone who already knew.

The Madonna's mantle reads as near-black. Whether it was ever blue depends on what Raphael mixed, and what that mixture did over five hundred years. Image from: Madonna and Child Enthroned with Saints, Raphael (Raffaello Sanzio or Santi) (Italian, Urbino 1483–1520 Rome), 1504. Oil and gold on wood.

The room where it was transmitted:

Vespasiano da Bisticci ran the most important bookshop in 15th-century Florence. His clients were popes and princes. His books were made by hand — copied by scribes, illuminated by miniaturists who ground their own pigments and mixed their own inks, bound in materials that required their own set of mineral and chemical knowledge to work correctly. The shop was also a workshop. The knowledge it contained was not only in the texts on the shelves but in the hands of the people producing them.

I am reading Ross King’s account of Vespasiano right now — The Bookseller of Florence — and what strikes me is how precisely the material knowledge of that workshop maps onto what Cennini was describing a few decades earlier in a different room across the same city. The illuminators working for Vespasiano were making the same decisions about the same minerals as the painters. Azurite or lapis. Which blue for which passage. How fine to grind. Which medium. The manuscript tradition and the painting tradition were drawing from the same empirical well.

Then the printing press arrived.

By 1480, Vespasiano’s workshop was finished. The technology that replaced it was faster, cheaper, and capable of reaching readers who could never have afforded a hand-copied manuscript. What it could not do, at least not immediately, was transmit the embodied knowledge of the people who had been making those manuscripts. The scribes scattered. The illuminators found other work or didn’t. The accumulated material intelligence of several generations of practice — what pigment survives parchment, what ink eats the page, what blue holds and what blue shifts — began to exist only in the hands of whoever still had it, which was fewer people every decade.

The same rupture happened to the painting tradition in 1841, when Winsor & Newton began selling pre-ground pigments in metal tubes. The grinding room started to empty. The apprentice who had spent years watching azurite lose its color under the muller, who had learned by failing and adjusting and failing again, was no longer necessary. You could buy the color already made, already stable, already optimized by a manufacturer who had done the mineralogy so the painter didn’t have to.

Both disruptions were called progress. Both were. But both also severed something that had been accumulating for a very long time — quietly enough that most people didn’t notice until they went looking for what was gone.

(left) Testing new ink on Claire Fontaine paper, (middle) black walnut ink on watercolor paper, (right) custom font ideas for the Brilliance exhibit at NHMLA.

You Already Know This

You have never ground a pigment. Probably. You have never matched a nib to a paper by feel, never watched a blue go gray under the muller, never held a piece of parchment up to the light to read the fiber before committing ink to it. Most people haven’t. That’s not a failure of education. It’s just the condition of living downstream of two disruptions — the printing press and the paint tube — that made those skills unnecessary for most purposes and invisible to almost everyone.

But you know something about this anyway.

You know it if you’ve ever chosen the wrong paper for a printer and watched the ink bleed. You know it if you’ve painted a wall and learned that the cheap roller leaves a texture the expensive one doesn’t. Or maybe you’ve just cooked with a cast iron pan long enough to stop treating it like every other pan — it holds heat differently, it needs different handling, and it rewards that attention in ways a non-stick surface never asks of you. None of that is mineralogy. All of it is the same epistemology — knowledge built through contact with a material that has its own properties, its own responses, its own way of recording what you did to it.

The painters knew this at a scale and depth most of us will never approach. But the knowing itself is not foreign to you. You’ve been doing a version of it your whole life. The formal vocabulary came much later, after most of the hard work was already done.

Here is what the hard work left behind. Not finished objects. Not frozen moments. The paintings in the great collections of Europe are still doing what the materials were always going to do — changing, reacting, recording. The painters set them in motion. They haven’t stopped.

Francesco Granacci (Italian, 1469–1543). Image from: Scenes from the Life of Saint John the Baptist, ca. 1506–7. Tempera, oil, and gold on wood, 30 9/16 x 59 1/2 in. (77.6 x 151.1 cm). The Metropolitan Museum of Art, New York.

They are running experiments. The lead white passages are slowly growing crystals that were never part of the original paint layer — lead soaps forming as the pigment reacts with the oil binder over centuries, migrating toward the surface and creating physical protrusions visible under microscopy. The smalt skies are losing their blue as potassium leaches out of the glass network and the cobalt coordination environment shifts. The vermilion passages in some paintings have been converting to metacinnabar for three hundred years and will continue to do so. The conservation scientists at the Rijksmuseum, the Getty, and the National Gallery are not preserving finished objects. They are monitoring ongoing transformations in materials that were set in motion the day the last brushstroke dried.

The painters knew transformation was coming. They didn’t know the mechanisms. But they made choices — about which pigments to trust, which grounds to use, which media to bind with — that reflected centuries of empirical observation about which materials held and which didn’t. The ones that held are the ones we still have. The record of their judgment is the survival of the object.

This isn’t a metaphor. A materials selection process, conducted over generations, tested by time — the proof is that you can stand in front of a Raphael Madonna more than five hundred years later and see more or less what he saw. The azurite has shifted in some passages. The lapis held. He knew it would.

Science builds on what came before. Art earns its keep by breaking it. I’ve spent my career on the first and watched the second from a safe distance — until I didn’t.

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What I Took From It

I watched it on a screen. Julie’s installation, the borax dying, the tincalconite forming in its place. Two true things that didn’t add up to a single clean answer.

I’ve been thinking about that ever since.

Science taught me to build. Each experiment grounded in the last one, each claim supported by the previous one, the whole structure load-bearing, accountable, and slow. That’s not a complaint. That’s how it’s supposed to work.

But there’s a version of science I was taught that I’ve never actually seen practiced. The clean sequential steps. The neutral observer. The hypothesis that waits patiently for its test. No scientist I know works that way. You follow a hunch. You ruin an experiment and learn something the successful version never would have shown you. You find the answer to a question you weren’t asking. The method is the story you tell afterward, not the account of what it felt like to find it.

I was told to stay in my lane. My advisors weren’t wrong about focus. But everything that has mattered in my work has been at the edges — in the gaps between disciplines, in the places the map marked as uninteresting, in the questions nobody in my field thought to ask because they were arriving from the wrong direction. I kept going there anyway. I’m still going there.

I stopped shrinking the question to fit the lane.

Watching Julie’s borax become tincalconite, I felt something I hadn’t expected. Not recognition exactly. Something adjacent to it. The material followed its conditions somewhere nobody planned for it to go.

I don’t know what’s forming on the other side of this. I just know the old structure is losing water molecules.

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I am the Curator of Mineral Sciences at the Natural History Museum of Los Angeles County, a former scientist at NASA’s Jet Propulsion Laboratory, and an adjunct professor at USC. I write Pocketful of Χtals because mineralogy is stranger and more alive than most people have been told.

If this post put something in your head you can’t fully resolve, that was the intent. Share it with someone who would argue with you about it.