IN PICTURES: Day two of the Papal Conclave

Black smoke billowed from the chimney of the Sistine Chapel earlier today, meaning Roman Catholic cardinals did not elect a pope in their second or third rounds of balloting.

Cardinals voted twice todayin Michelangelo's famed frescoed chapel after a first vote Tuesday in a conclave to elect a successor to Benedict XVI, who stunned the Catholic world last month by becoming the first pope in 600 years to resign.

IN PICTURES: DAY TWO OF THE PAPAL CONCLAVE

(Picture: AP/Oded Balilty)

Visitors wait for the chimney smoke in St. Peter's Square

(Picture: AP/Michael Sohn)

Another view of the crowds in front of St. Peter's Basilica

(Picture: AP/Michael Sohn)

The Vatican has revealed what the smoke signals emerging from the Sistine Chapel chimney are made of, after the stir caused by how much more distinct the black smoke in the conclave has been compared to the past.

(Picture: AP/Alessandra Tarantino)

Spokesman the Rev. Federico Lombardi said the black smoke indicating a pope had not been elected was made by adding cartridges containing potassium perchlorate, anthracene (a component of coal tar), and sulphur to the burned ballots.

The white smoke signalling a pope has been elected is produced by potassium chlorate, lactose and chloroform resin.

The Vatican is burning the flares following confusion in past conclaves about smoke colour.

The Rev. Lombardi said that neither the chapel frescoes nor the cardinals inside suffered from the smoke.

(Picture: AP/Oded Balilty))

Nuns walk in the Bernini Colonnade in St. Peter's Square

Seagull waits for #Conclave smoke pic.twitter.com/iSKPt5fXXA

— anthony murnane (@anthonymurnane) March 13, 2013

A gull takes a break atop the chapel chimney

(Picture: AP/Emilio Morenatti)

A barefoot faithful kneels in prayer

(Picture: AP/Andrew Medichini)

Former NBA star Dennis Rodman walks next to the Bernini Colonnade

Fresh from his triumphant diplomatic tour of North Korea, Rodman rocked up in Rome today to promote the papal candidacy of Cardinal Peter Turkson of Ghana.

"I want to be anywhere in the world I'm needed," The Guardian reported him as saying.

MORE: CNN live camera link to Sistine Chapel chimney