* Mozambique's ruling party turns 50
* Opulent celebrations belie widespread poverty
* Mining, gas boom transforming war-scarred economy
By Marina Lopes
PEMBA, Mozambique, Sept 30 (Reuters) - It was billed as a celebration of its socialist revolution, but when Mozambique's ruling Frelimo party marked its 50th birthday this week, Marx came a distant second to Money.
Reflecting their anti-colonial, revolutionary roots, Frelimo leaders pointedly chose a venue in the untamed corner of southern Africa where half a century ago guerrillas launched the uprising that would lead to independence from Portugal in 1975.
But beyond the symbolism of the location, in the northern province of Cabo Delgado, the obligatory use of "Comrade" and the AK-47 rifle that still adorns the national flag, everything at the party congress pointed to the huge wealth accruing to the political elite in the fast-growing energy producer.
The venue itself was a lavish complex of VIP reception rooms and cavernous dining areas, set amid a village of apartment units, two on-site banks and a hospital clinic for 2,000 guests.
Just to the north lies the Rovuma Basin, where U.S. energy firm Anadarko and Italy's Eni are exploring some of the world's biggest untapped natural gas reserves - an estimated 130 trillion cubic feet, or enough to supply Western Europe for over a decade.
To some of Mozambique's 23 million people, the talk of "revolutionary war" by Frelimo leader and President Armando Guebuza - known as "Mr. Guebusiness" on account of his huge commercial interests - rings hollow.
"It is absurd to spend $8 million on a week-long conference when people are starving a block away," said Rudiger Franck, a hotel owner and Frelimo party member in Pemba, the run-down seaside town that hosted the seven-day jamboree.
"It gives the impression that the party has lost touch with the reality of life for most of its members."
Under its first president, U.S.-educated sociologist Eduardo Mondlane, Frelimo struck out on a Marxist course until 1990 when, tired from civil war and under growing pressure from the West, it renounced socialism.
In the last decade, mostly under Guebuza, Mozambique has become a hotbed of foreign mining investment that has lifted economic growth to 7 percent a year and in 2011 made its currency the strongest performer against the dollar.
Brazil's Vale, for instance, has poured $2 billion into a coal mine in the northwestern region of Moatize and plans to invest $6.4 billion in the years to come.
Frelimo says all Mozambicans stand to benefit, yet in a country where the average person scrapes by on $400 a year, the opulence of its congress sends a conflicting message.
"This money never reaches the people. It remains in Frelimo's pocket," said Mustagibo Bachir, a Cabo Delgado member of parliament for Renamo, Frelimo's foe during a 16-year post-independence civil war.
Bachir sees a worrying precedent in the handling of the ruby and timber sectors in the north, which remains one of the country's poorest regions.
"Our people still don't have access to water, food or jobs," he said.
Besides Renamo, Frelimo is also facing opposition from the upstart Mozambican Democratic Movement (MDM), run by the 48-year-old mayor of Beira, Mozambique's second city with a population of half a million people.
Analysts say elections due in 2014 are too soon for MDM to make serious headway, but point to its popularity with young, educated and unemployed Mozambicans as a sign that it could become a force to be reckoned with later in the decade.