To lighten the mood deep down in the San José Mine, the 33 trapped miners would playfully imitate Leonardo Farkas Klein, donning makeshift wigs to simulate the long curly blond mane of the mining executive.

"Farkas," as everybody in Chile's mining industry calls him, gained international fame by helping save the miners' families with generous donations of $10,000 each — even before rescuers pulled the men to the surface more than two months after the cave-in.

With his custom-designed Zegna suits, pink tie with matching Brioni handkerchief and colored diamond cufflinks — as he dressed on the night he held a dinner to meet the miners — Mr. Farkas is an original in this conservative South American country. He made millions of dollars as an entertainer in Las Vegas and on cruise ships, married well, and then returned to his native Chile five years ago to try his hand in the profession his late father loved: mining. 

Since then, the former piano bar singer has become a national sensation in Chile, but less so for his mines than for his eccentric personality, wild parties and seeming heart of gold. He has become Chile's most prominent philanthropist, contributing millions of dollars to help needy Chileans, as well as earthquake victims in Chile and Haiti.

While that has endeared him to the country's poor, the public nature of his gift giving and his outsize personality have made him plenty of enemies among the buttoned-down Chilean elite. When he flirted in 2008 with the idea of running for president, he became one of the most feared rich men in Chile because of his populist appeal.

"The business people here don't like me too much, I don't think I fit in here," Mr. Farkas, 43, said sitting in the nondescript office here of his Santa Fe mining company. "One day I may go back" to the United States. "But right now I think I can do more here with my money and work than in America."

Mr. Farkas boasts of having five Hummers, a private jet, a Caribbean island getaway, a wristwatch designed for him by Cartier at the request of Prince Albert of Monaco, even a Rolls-Royce Phantom Drophead convertible he says he paid $2.2 million for, thanks to heavy import duties and other fees. He paid more than $400,000 to be the first South American to travel into space as part of Richard Branson's Virgin Galactic tour next May.

MR. FARKAS'S parents, Jews of Hungarian descent, left Transylvania for South America in 1939 amid the growing Nazi threat. Daniel Farkas Berger, his father, made and lost two fortunes in the mining business, his holdings being nationalized by Brazil in the early 1950s and Chile in 1970, under the Socialist government of Salvador Allende. "My father always said money comes and goes," Mr. Farkas said. "That's why he said, 'Always enjoy life. Eat in the best restaurants, have the best clothes.' "

A passionate music fan, Mr. Farkas's father started his son on the piano at 2 years old. At 15, Leonardo put together a group of 15 musicians who played weddings and toured in Argentina, Brazil and Peru.

JUST before he turned 21, he moved to the United States, where he performed in the Catskills and Miami, playing in small clubs, and then on cruise ships. Unable to afford other musicians, he used much of the $10,000 he brought from Chile to buy 15 keyboards and called himself "The Orchestra Man."

He was frugal back then, depositing much of his earnings in his mother's Miami account so he could not spend it. "I never wanted to be famous," he said. "I always wanted money."

By 24, he had made his first million dollars, he said. Then at 27, while performing in the Catskills at the Concord Hotel, he met Betina Friedman Parker, an heiress to the Concord hotel fortune. A year later they married and took a six-month honeymoon around the world.

The couple moved to Las Vegas, where Mr. Farkas performed at the MGM Grand with Tom Jones. They played blackjack into the early morning and ate steak and eggs before going to bed at 6 a.m.

"My wife didn't like it there," he said. "So I had to choose the marriage or Vegas. I decided to choose my marriage."

In 1995 they moved to Boca Raton, Fla., where they had two of their three children. Mr. Farkas retired and took up golf and tennis, but he grew bored and felt the need to do something "bigger." When his father died in 2004, he decided it was time to go home.

"I told my wife, 'We need to go back to Chile, I am going to fulfill my father's dream, which was to go back to the iron,' " he said.

At first she was skeptical. "My kids didn't speak Spanish when we came," he said. But he persuaded her, he said, by saying they would stay only two years.

He built a large home overlooking Santiago with 24-carat-gold-trimmed tiles in the swimming pool. He threw outlandish parties, including a 15th wedding anniversary celebration for 200 guests last November that cost $4 million and involved 600 entertainers, including Brazilian carnival dancers, and the musical acts Donna Summer and Air Supply.

And he fulfilled his father's dream of making it in mining. Today, he has four mines that export a total of three million tons of iron ore a year, all to China, he said. Two of his mines are within three miles of the San José Mine.

He says working in Chile's mining areas brought him closer to the country's poor and inspired him to do more charity work. He now supports 16 orphanages for young girls. He makes many donations out of pocket without seeking a tax break, local politicians said, and is known for handing 5,000-peso bills (about $10) to strangers on the street and for tipping exorbitant amounts in restaurants.

Here in northern Chile he was the first mine owner in the area to pay his 3,200 employees "an ethical wage, when other businessmen didn't," said Brunilda González, the mayor of Caldera. After joining forces with Mr. Farkas, Caldera built about 900 homes between 2006 and 2007, more government-assisted housing per capita than any other community in the country, she added.

"His philosophy is, 'God has given me a lot, so I'm going to give double,' " she said. "If he could solve poverty alone, he would."

In 2008 he drew national attention when he donated about $2 million in the annual Telethon for handicapped children — an unheard of amount.

Rather than gratitude, however, his public philanthropy has earned him the enmity of the traditional business elite in Chile, where charity work, hewing to the country's strong Catholic backbone, is normally done with more discretion. It does not help that Mr. Farkas is openly critical of Chile's upper class. "The rich people in Chile are very stingy, and all over South America," he said.

LIFE got more difficult when speculation — fueled to some extent by him — swirled about a presidential run in 2009. He soon found himself embroiled in a nasty business dispute in which he was accused of using company money in his philanthropy. Tired of the negative publicity, in December 2008 he announced he would not run. He settled lawsuits related to the donations in early 2009, but the experience left him bitter and suspicious that the suits had been politically motivated.

"I should never have said I would consider being president of Chile," he said. "That created enemies from all over. The businessmen want me out, they are happy the way they are."

Mr. Farkas says he is now considering offers from companies to buy a majority of his mining assets, so he can concentrate more on philanthropy.

"I am not so happy working so much, it is very stressful," he said. "This year I have donated over $20 million. Not bad for a guy that used to play for $50 for happy hour at the Marco Polo Hotel in Miami Beach, right?"

Aaron Nelsen contributed reporting from Santiago, Chile.