How Cellini cast the Perseus
and nearly lost everything
The furnace failed. The metal was solidifying. He threw his pewter plates in and prayed.
On a winter night in 1545, Benvenuto Cellini came closer to catastrophic failure than at any other point in his career. The bronze for the Perseus — nine years of work, a commission from the most powerful man in Florence — was solidifying in the mould before it had fully filled it. The furnace was ruined. His assistants were fleeing. And Cellini, fifty-five years old, feverish and exhausted, ran back inside and started throwing his pewter dinner plates into the metal.
It worked. The Perseus was saved. And that night became one of the most famous passages in the history of art writing — because Cellini himself wrote it down, in exact detail, twenty years later.
Nine years in the making
Cosimo I de' Medici commissioned the Perseus in 1545. The subject was politically deliberate: Perseus standing over the severed head of Medusa, a symbol of the Medici's triumph over their enemies. Cosimo wanted it for the Loggia dei Lanzi in the Piazza della Signoria, the most public space in Florence, where it would stand beside Donatello's Judith and Holofernes and — eventually — Michelangelo's David.
The pressure was enormous. Cellini knew exactly what was at stake. He spent years on the preliminary models in wax and clay, refining the composition and working out the technical problems of casting a full-scale bronze figure. A bronze this size, cast in a single pour, was at the outer edge of what was technically possible in the sixteenth century.
What went wrong
The casting was scheduled for the evening. Cellini had been ill for days with a fever. His assistants were nervous; this was the most complex and expensive casting any of them had attempted. The furnace was loaded with metal — copper and tin in the right proportions for bronze — and the fire was lit.
Then the furnace cracked.
The moisture in the clay, inadequately dried, turned to steam when the temperature rose and split the furnace lining. The fire began to fail. The metal in the crucible, which needed to reach around 1000 degrees Celsius to remain liquid, started to cool. In the mould below, the figure was only partially filled. If the metal solidified now, the casting was lost. Nine years of work, and the commission, and Cosimo's patience — all of it gone.
What he did
Cellini's account of what happened next is worth reading in his own words, but the short version is this: he ordered his assistants to feed oak logs into the furnace as fast as they could, drove them with what sounds like considerable force of personality, and sent to his house for every piece of pewter he owned — plates, bowls, cups, two hundred pieces in total — and threw them into the crucible.
The tin in the pewter lowered the melting point of the alloy. The metal became fluid again. The mould filled.
"When I uncovered the mouth of the mould I found that the bronze had filled it to perfection. I knelt down and gave thanks to God with all my heart."
The figure was not perfect — the right foot of Perseus was missing, and had to be cast separately and attached. But the body, the severed head, the whole composition: complete. Cellini had saved it.
What the Perseus is
You can see it today in the Loggia dei Lanzi, exactly where Cosimo placed it in 1554. It is a bronze figure standing roughly three and a half metres tall on a base decorated with relief panels and small bronze figures. Perseus holds the head of Medusa high in his right hand. Medusa's body lies beneath his feet, blood still flowing in bronze from the severed neck.
The technical accomplishment is staggering. The extended arm with the raised head, the dynamic pose, the details of the armour and the wings — all cast in a single pour of bronze, hollow, exactly as Cellini planned. It has stood outside for nearly five centuries. It is still there.
Why he wrote it down
Cellini was in his late fifties when he dictated his autobiography. He had been accused of sodomy, lost favour at the Florentine court, and was living under something like house arrest when he began speaking his story to a young apprentice who wrote it down.
He wanted the world to know what he had done. Not the official version — not the polished story of a craftsman serving his patron. The real version: the fever, the cracked furnace, the pewter plates, the terror and the recovery. He wanted people to understand what it actually cost to make a thing like the Perseus.
That is why the autobiography still matters. Not because it tells us about Renaissance art history. Because it tells us, with complete honesty, what it is like to be the person making something — and to come within minutes of losing everything you have worked for.
This account draws on Cellini's own autobiography. To read the full story in his words, in a modern English translation that keeps his voice intact:
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