Cupric Nitrate

The formula was copper nitrate trihydrate dissolved in distilled water at a concentration of approximately forty grams per liter, which produced a solution the color of blue Curacao, a vivid aquamarine that looked nothing like the green it would become on the bronze, because the color of the solution was the color of the copper ions in suspension and the color of the patina was the color of the copper ions bonded to the bronze surface and these were different things, chemically and visually, the way the color of paint in the can was different from the color of paint on the wall, the medium changing the expression.

Oren mixed the solution on a Friday morning.

He measured the copper nitrate crystals on the digital scale — the small precise scale that he used for chemicals, not the large floor scale that he used for bronze ingots — and he dissolved them in distilled water in a glass jar and he stirred with a glass rod until the crystals were completely dissolved and the solution was clear and blue and uniform, and then he covered the jar with a lid and set it on the workbench beside the liver of sulfur and the other chemicals and the jar sat there like a small window into a tropical sea, incongruously beautiful in the grimy environment of the studio.

The memorial bronze had been resting for two days since the liver of sulfur base coat.

The resting time was necessary because the base coat needed to cure, needed to bond fully with the bronze surface, needed to become stable before the next layer was applied, the way a foundation needed to set before a building was constructed on it, and Oren had used the resting time to work on the re-investment of the New York leg section at the foundry, applying two coats of ceramic shell per day, the work proceeding on its own timeline, the memorial and the commission advancing in parallel like two trains on adjacent tracks, each one moving at its own speed toward its own destination.

Lina was on the stool again.

She had established this as a practice now, the stool in the doorway, the tea, the book, the watching, and the practice had the quality of a ritual, a regularly scheduled encounter between herself and the work, and Oren had accommodated the ritual the way he accommodated all of Lina's rituals, by adjusting his own practice slightly, working a little more slowly, explaining what he was doing as he did it, not in the instructional manner of a teacher but in the conversational manner of a person sharing a room with someone they loved, the commentary a form of companionship rather than education.

He heated the bronze.

The base coat responded to the heat by darkening slightly, the brown-black becoming a fraction richer, and this was good, was expected, the liver of sulfur continuing to develop even after the rinsing, the residual chemical deepening over time the way a stain deepened in wood, and the darkened surface was ready, was open, was waiting for the green.

He picked up the spray bottle.

For the cupric nitrate he used a spray bottle rather than a brush, because the spray produced a finer, more even application than the brush, a mist of tiny droplets that landed on the hot surface and reacted individually, each droplet producing its own small bloom of green, the thousands of blooms merging into a field of color that had the complexity of a natural surface, the unevenness of weather, the randomness of time.

He sprayed.

The blue solution hit the hot bronze and something happened that never failed to arrest him, no matter how many times he had seen it — the blue droplets turned green on contact. The copper ions in the solution bonded with the copper in the bronze and the sulfur in the base coat and the oxygen in the air and formed a new compound, a copper hydroxyl sulfate, and this compound was green, was the green of patina, was the green of the Statue of Liberty and the rooftops of Copenhagen and the doors of the Baptistery in Florence, the green of oxidized copper, the green of time.

The green appeared in patches.

Not a uniform field but a scattered constellation of green blooms on the dark base, each bloom a different intensity depending on the amount of solution that had landed in that spot and the temperature of the bronze beneath it and the thickness of the base coat and the dozen other variables that made each bloom unique, and the overall effect was dappled, mottled, alive with variation, and this variation was the art, was the thing that separated a good patina from a paint job, because a paint job was uniform and a patina was not, and the eye knew the difference, the eye that had evolved over millions of years to detect patterns could also detect the absence of the right kind of randomness, the uncanny evenness that said: this is manufactured, this is controlled, this is not real.

Oren sprayed again.

He built the green in layers, each spray adding density to the blooms, deepening the color, extending the coverage, and between sprays he brought the torch close and the heat accelerated the reaction and the green intensified, and then he misted the surface with clean water and the water cooled the bronze slightly and the thermal change added another variable to the chemistry and the surface became more complex, more layered, more like the surface of something that had been in a garden for thirty years rather than something that had been in a studio for thirty minutes.

He told Lina what he was doing as he did it.

He said, The spray gives me the randomness. If I used a brush the green would be too even. Too controlled. The spray lets the chemistry decide where the green goes.

She said, You give up control.

He said, I give up some control. I control the overall density, the concentration of the solution, the temperature. But the exact placement of each bloom is the chemistry's decision, not mine.

She said, That sounds like trust.

He said, It is trust. You trust the materials to do what they do. You set up the conditions and then you let the reaction happen.

She was quiet for a moment and then she said, That is what the treatment is. Setting up the conditions and letting the reaction happen.

He did not respond because the parallel was exact and the exactness of it cut through the surface he maintained in the studio, the professional surface, the surface of the patinator at work, and beneath that surface was the other reality, the reality of the treatment and the chemicals and the trust that the chemicals would do what they were supposed to do, and this trust was fragile, was tested every two weeks, was confirmed or denied by the body's response, by the scan results, by the numbers on the blood work, and the trust never became certainty, was never more than trust, which was to say it was never more than the willingness to proceed without guarantees.

He applied the second spray of cupric nitrate.

This time he varied the distance, holding the bottle farther from the surface in some areas and closer in others, and the variation in distance produced variation in droplet size, the far drops fine and dispersed and the close drops coarse and concentrated, and the result was a surface of mixed textures, the fine areas producing a soft, diffuse green like moss and the coarse areas producing a brighter, more defined green like verdigris on a rain gutter, and the two textures side by side created the depth that Oren was after, the sense of layers, of time, of multiple events written on the same surface.

By noon the exterior of the memorial was green.

Not uniformly green — the base coat showed through in places, the dark brown anchoring the green the way the earth anchored the vegetation, and the high points of the form were greener than the low points because the spray hit the high points first and hardest, the way rain hit the high points of a sculpture first and hardest, and this hierarchy of color — green on the prominences, dark in the recesses — was the hierarchy of natural patination replicated in artificial patination, the simulation of physics, the patinator's imitation of weather.

He stopped to assess.

Assessment was the critical pause, the moment when the hand stopped working and the eye took over, and the eye was a different judge than the hand, was more critical, more detached, could see the whole where the hand could only feel the part, and Oren stepped back from the worktable and looked at the memorial from arm's length and then from three meters and then from the doorway where Lina sat, each distance revealing a different aspect of the surface, the close view showing the individual blooms and the medium view showing the texture and the far view showing the overall color, and each distance had to work, had to convince, had to say old and natural and weathered, and Oren assessed each distance and found that the close view was good and the medium view was good and the far view was almost good but needed more density in the upper quadrant, where the spray had been too light, and he noted this and returned to the worktable and corrected it with two more passes of the spray bottle, and then the far view was good too.

He said to Lina, That is the first green. It needs to dry overnight. Tomorrow I will do the interior and then a second pass on the exterior.

She said, The interior too.

He said, The inside of the vessel will be visible. The patina has to run across both surfaces. Inside and outside. The viewer should not be able to tell where one ends and the other begins.

She said, Continuity.

He said, Continuity. The patina does not know about inside and outside. The chemistry treats all surfaces the same. The only difference is how the light hits them.

She stood from the stool and walked to the worktable and looked at the memorial and the green was on it, the first green, the beginning of the surface that would be the final surface, and the bronze was no longer raw, was no longer the penny color of the pour or the dark of the liver of sulfur, was becoming the thing it would be, the memorial, the vessel in the garden, the object that would hold the space where Margherita had been.

She said, It looks like the earth. Like a piece of the earth that has been shaped.

He said, That is the idea. The patina is the bronze returning to the earth. The green is copper becoming copper carbonate becoming something closer to the stone and the soil it came from. The patina is the metal going home.

She looked at the green bronze and he looked at her looking at the green bronze and the triangle of looking — Oren to Lina, Lina to bronze, bronze to — what? To the air, to the light, to the future viewer in the garden, to the memory of Margherita, to the idea of memorial itself — the triangle was the structure of the moment, was the geometry of making, the maker and the witness and the made thing forming a relationship that was older than language, that went back to the first time a person made a mark and another person looked at it and the mark became more than a mark, became a communication, became a surface that carried meaning from one consciousness to another.

They went upstairs for lunch.

In the afternoon Oren returned to the studio and applied the cupric nitrate to the interior of the memorial, spraying the inside surfaces with the same technique, the spray and the torch and the water and the patience, and the interior was harder because the light was different inside the vessel, the shadows deeper, the surfaces more concave, and the spray behaved differently on concave surfaces, the droplets pooling in the hollows rather than dispersing, and Oren had to adjust, had to tilt the vessel, had to use the torch more aggressively to evaporate the pooling, and the adjustment was the skill, was the experience, was the thirty-one years speaking through the hands.

By five the interior was done.

The green ran across both surfaces now — outside and inside, convex and concave, light and shadow — and the continuity was there, the patina flowing from one surface to the other without interruption, without seam, the way water flowed over a stone without distinguishing between the top and the sides, and this continuity was what Oren had told Valentina about, the merging of inside and outside, the ambiguity that was the memorial's meaning.

He set the memorial on the rack to dry overnight.

The drying was important because the chemicals were still active, still reacting, still developing the color, and the overnight drying allowed the reactions to reach their equilibrium, the green settling into its final character, the variations stabilizing, the surface finding its resting state the way a body finds its resting state after exertion, the chemistry slowing, the color deepening, the surface becoming what it would be.

Saturday morning he applied the second green.

This pass was lighter, a veil rather than a coat, the spray held farther from the surface, the droplets finer, the purpose not to add coverage but to add complexity, to layer a slightly different green over the first green, the way a glaze in oil painting layered one transparent color over another to produce a third color that neither could produce alone, and the second green was bluer than the first, the solution slightly more dilute, the reaction slightly cooler, and the blue-green over the yellow-green produced a visual depth that read as age, as accumulation, as the record of multiple seasons of oxidation on a single surface.

Lina was on the stool.

She watched and he worked and the morning passed in the particular time of the studio, which was not clock time but process time, measured not in hours but in coats and drying periods and assessment pauses, and this process time was slower than clock time and faster than clock time simultaneously, the way time in a hospital was both slower and faster, and Oren lived in both times now, the process time of the studio and the treatment time of the hospital, and the two times overlapped and intersected and sometimes coincided and sometimes diverged, and the divergence was the hardest part, the moments when the studio time said slow down and the treatment time said hurry.

By noon the second green was done.

He assessed it from every distance and the surface was developing, was becoming complex, was approaching the state he was aiming for but had not yet reached, because the state he was aiming for required at least one more green pass and then the ferric nitrate highlights and then the ammonia fuming and then the seal, and each of these steps was a separate day, and the total time was still a week, and the week stretched ahead of him like the autostrada, a known distance to a known destination.

Sunday was a drying day.

He did not enter the studio. The memorial dried on its rack and the chemistry continued its slow work in the dark and the Sunday passed in the domestic time, the time of Lina and the apartment and the town, and they walked to the market and bought vegetables and bread and Oren cooked his roast chicken with lemon and rosemary and the chicken was good and the evening was warm and the windows were open and the green was developing in the studio below, invisible, autonomous, the surface becoming itself without the maker's intervention, which was perhaps the most important part of the process, the part where the maker stepped away and let the material find its own truth.

Monday was the third green pass and the ferric nitrate highlights.

Tuesday was the ammonia fuming.

Wednesday was the wax seal.

And each day Lina was on the stool in the doorway, watching, present, bearing witness to the surface as it came into being, and her presence changed the work in a way that Oren could not have predicted, made him more attentive, more deliberate, more aware of what he was doing and why, because the explaining — the running commentary that her presence drew from him — forced him to articulate things he had never articulated, to put into words the decisions that had always been wordless, the instincts that had always been instincts, and the articulation changed the instincts, refined them, made them more precise, the way naming a color made the color more visible.

She was changing his work by watching it.

This was a form of collaboration that had no name, was not a partnership or an apprenticeship or a supervision but was something else, was the influence of attention itself, the way the observed changed under observation, the way the watched surface became a different surface from the unwatched surface, not because the watcher intervened but because the watcher's presence altered the conditions of the making, the way humidity altered the conditions of the drying, the way temperature altered the conditions of the reaction.

By Wednesday evening the memorial was complete.

The patina was done. The green was deep and varied and complex and the dark base showed through in the recesses and the warm ferric nitrate highlights glowed on the high points and the ammonia fuming had given the whole surface a depth, a darkness behind the green, that read as great age, as decades of exposure, as the slow chemistry of the Italian climate working on the bronze, and the wax seal had locked it all in, had given the surface the low sheen of something cared for, and the memorial sat on the worktable and it was finished and Oren stood back and looked at it and Lina stood beside him and looked at it and neither of them spoke because the surface was speaking for itself, was saying what the green always said, which was: I was here, I was exposed to the world, I was changed by the world, I am the record of the changing.

Lina said, after a long silence, It is the green of things that are still alive.

She was quoting Valentina Conti's description of her mother's words, and Oren heard the quotation and understood that the green of the memorial had achieved what it was meant to achieve, had become not just a color but a meaning, not just a surface but a statement, and the statement was the one that Margherita had made in her garden among the lemon trees and the rosemary and the jasmine — that green was the color of between, of still, of not yet over.

He did not cover the memorial with the cloth.

He left it uncovered on the worktable, the green surface visible in the studio, and the green was there when he came down in the morning and there when he went up in the evening, and the green was part of the studio now, part of the daily visual environment, and Oren looked at it and the looking was not assessment anymore but companionship, the way you look at something you have made that has become something other than what you made, something that belongs to itself now, something that will go on without you.