How They Make The White Or Black Smoke That Announces The New Pope

The secretive election process to select the next Pope officially began on Tuesday at the Vatican's Sistine Chapel.

To those watching in the Vatican Square, the results of each vote are announced by smoke that emanates from the Sistine Chapel's chimney. The smoke is black if no pope has been elected. The smoke is white if a pope has been elected.

For example, the smoke was black today after the first round of votes, which means no consensus has been reached among the 115 voting Cardinals yet.

We've previously explained how the voting process works, but what actually makes the smoke black or white?

First, the chimney is connected to two stoves inside the chapel. According to "The New York Times'" Henry Fountain, one stove burns the paper ballots of the Cardinals after the votes are counted.

The other stove releases either white or black smoke, which combines with the smoke from the burning paper ballots before it comes out of the chimney.

The conclave uses cartridges filled with different chemicals to produce either white or black smoke, according to the Times. It is still not known what those chemicals are.

The director of a smoke-machine supplier in England, Ben Baxter, gave the Times a few suggestions as to what the chemicals are:

The principal chemical was most likely potassium chlorate, which ignites easily — a 9-volt battery will do — and produces fine white particles as it burns. “That’s what we sell in our smoke pellets and smoke grenades,” Baxter said.

A black cartridge probably uses potassium chlorate too, he said, along with a dye to coat the particles. “It’s less nasty than anything that would create black smoke in the olden days,” he said.

A two-thirds plus one majority is required to elect the Pope. The whole process is extremely well-guarded. The Cardinals are completely cut off from the outside world, locked inside the Sistine Chapel until a decision is made. No TV, radio, newspapers or texts are allowed. We assume the mystery of the chemical mix that gives the smoke its color is to maintain that policy of secrecy.