One of the most influential early European accounts of Chinese porcelain production was written by a priest, in two unusually detailed letters.

His name was François Xavier d'Entrecolles — Père d'Entrecolles to history — a Jesuit missionary who arrived in China around the turn of the eighteenth century and worked in the region around Jingdezhen. In 1712, and again in 1722, he wrote home with observations on the materials, labour and kilns behind the porcelain Europe admired. Meissen had already produced European hard-paste porcelain by 1710, so the letters did not "give" Europe porcelain; they helped make Jingdezhen's production system more legible to European readers.

What Europe would pay

To understand what that letter was worth, you need to understand the porcelain mania of the time. For two centuries, European elites had been paying staggering sums for Chinese porcelain — a material nobody in Europe could reproduce or even properly explain. Theories abounded: it was made from crushed seashells; it was buried underground for a century to cure; it was a kind of alchemical glass.

Augustus the Strong, Elector of Saxony, described his own collecting as a maladie de porcelaine — a porcelain sickness. He wasn't exaggerating: in 1717 he traded six hundred of his own dragoons — actual cavalry soldiers — to the King of Prussia for a set of 151 Chinese vases. The vases are still known as the Dragoon Vases. The Medici in Florence had tried to fake porcelain back in the 1570s and produced only a soft, cloudy imitation. The Dutch gave up on the material entirely and copied the look instead — blue-painted earthenware from Delft, flattery in tin glaze.

Augustus took the direct approach: he imprisoned an alchemist named Johann Friedrich Böttger in a castle and ordered him to solve porcelain instead of gold. Böttger, working with the scientist von Tschirnhaus, actually succeeded around 1708–1710 — the founding of Meissen, Europe's first true porcelain works. But Meissen guarded its arcanum as jealously as the Chinese had, and the rest of Europe was still locked out.

The man inside the city

Meanwhile, d'Entrecolles was living where every alchemist in Europe would have sold his soul to spend a week. Jingdezhen at the time was one of the great industrial cities on earth — a million people by some period accounts, three thousand kilns, the night sky glowing with fire. An observer of the era described it as "one vast furnace with many vents of flame."

D'Entrecolles had two advantages no European rival possessed: he spoke the language, and he had a pastoral flock that included porcelain workers. He was, by his own account, genuinely curious rather than commercially motivated — a man of the Enlightenment who believed knowledge should circulate. Over years, he watched, asked, cross-checked what workers told him against what he could read in Chinese texts, and toured workshops.

On September 1, 1712, he put it all in a letter to Father Orry, his order's treasurer in Paris.

What the letters said

The 1712 letter — and a second, more detailed one from 1722 — amounted to a procedural manual for the porcelain industry. He described the two-ingredient secret at the heart of the material: kaolin, the white clay dug near the village of Gaoling (his romanization gave the world the mineral's name), and petuntse, the porcelain stone that fuses glassy at high heat. He explained — via a metaphor he credited to his Chinese informants — that petuntse was the flesh of porcelain and kaolin its bones. He detailed the washing and aging of clay, the throwing, the trimming, the glazes, the kiln construction, the firing schedules, even the division of labor: the saying that a single cup passed through seventy or more pairs of hands.

The letters were published and excerpted across Europe, becoming part of a growing body of technical writing about porcelain. They mattered not as a single recipe that unlocked the material, but as an unusually rich description of how a specialised ceramic city organised knowledge, raw materials and labour.

The polite spy, reconsidered

Was it espionage? D'Entrecolles didn't steal documents or bribe officials; he described what an observant resident could see and what workers freely told him, and he published openly rather than selling to a crown. Call it the eighteenth century's most effective piece of technology journalism. From Jingdezhen's side of the story, of course, it reads differently: a millennium of accumulated craft advantage, transferred westward in two envelopes.

Here's the irony worth sitting with, though. Europe got the recipe — but the recipe turned out to be the smallest part of the craft. What couldn't be mailed was the city itself: the seventy-two specialized hands, the generational knowledge of how this glaze behaves at that cone in this corner of the kiln, the sheer concentrated density of skill that comes from a valley doing one thing for a thousand years. Meissen, Sèvres, and Stoke-on-Trent became great traditions in their own right. Jingdezhen just kept firing.

It still does. The clay is still dug from the same hills d'Entrecolles described. The standard is still the one his informants worked to. And the letters make a fine story to tell at a dinner table — ideally one set with porcelain from the city where they were written.