“Caieiras” a name echoing through time itself. The Fornos de Cal stand before us. They are silent witnesses to a bygone era.
These Fornos de Cal are more than just ruins. They are a cultural and historical attraction. They whisper tales of industry and inspiration. The image of these very kilns is etched onto the city’s coat of arms.
Back in the mid-19th century, a prominent figure named Coronel Antonio Proost Rodovalho acquired a vast area here. He was a strongman in São Paulo’s commerce and agriculture. His goal was to produce lime.
Rodovalho’s story began near the Juquery-Guaçu River. Here he cultivated grapes and raised livestock. During one of his visits he discovered minerals rich in calcium carbonate. It was perfect for lime production. Locals had already noticed it. This discovery was invaluable. Brazil was on the cusp of intense industrialization. The construction industry needed raw materials. The site where the minerals were stored became known as “Bom Sucesso”. This name was later adopted for the neighborhood.
These kilns played a crucial role in producing quicklime. This is calcium oxide created by heating limestone. The process occurs at very high temperatures around 1000 degrees Celsius.
Lime production was essential. Quicklime reacts violently with water releasing heat. This made transportation risky. Shipping limestone and processing it locally was a safer solution. The kilns used wood for fuel.
Limestone was layered with wood inside the kilns. The top was left open. This prevented steam build-up that would ruin the quicklime. The fire burned for about a week. Workers carefully removed the lime after it cooled.
The lime was then hydrated. Water was added to create a solution. This solution was used to make mortar. It was also used for whitewashing walls. Whitewashing was done by skilled professionals. Their lime preparation methods were often closely guarded secrets.
The most common recipes involved slowly adding water. The mixture was left to boil. Then, tallow or blue and white soap was added. Aniline was often added. It served to whiten the lime giving it a slightly bluish tint when fresh.
The Fornos de Cal before you stand deactivated now. However, they remain nearly intact. They are lasting monuments to the past. They remind us of Caieiras’ industrial roots. Take a moment to appreciate these historical landmarks. Think about the people who worked here. Imagine the fires burning bright. Consider the impact these kilns had on the region’s development.