Black smoke billowed from the chimney of the Sistine Chapel on Wednesday (May 7) evening, signaling an inconclusive first vote by cardinals locked in the Sistine Chapel in a conclave to elect a new pope. Olivia Zollino reports.

For white smoke, a compound of the chemicals potassium chlorate, lactose, and rosin (also known as Greek pitch) is used, while potassium perchlorate, anthracene, and sulfur are used for the black smoke.

This week, 133 cardinals have gathered in the Vatican to elect a new leader of the Catholic church. During their deliberations, the only indications of their progress are the regular plumes of smoke wafting from a freshly installed chimney perched on the roof of the Sistine Chapel.