June 6, 2006

Zeppelin seeks hidden diamond stashes in Kalahari

By Eric Onstad

JWANENG MINE, Botswana (Reuters) - Moonlight glistens off a
huge zeppelin airship as it glides over Botswana's Kalahari

High-tech sensors on board probe the arid sands below,
looking for buried diamonds.

This is De Beers' latest tool in its search for gems in
Botswana, the world's leading diamond producer by value.

The rigid dirigible with a disaster-scarred history carries
classified U.S. technology, first developed for the military
and still so sensitive that a photographer was warned not to
film the equipment, provided and operated by U.S. firm Bell

"This is the cutting edge. We're pushing geophysics to the
boundaries," said Brad Pitts, who heads De Beers' airship
exploration program, launched last November.

"This is the only airship in the world being used for
geophysical surveying."

The zeppelin, which has a metal frame unlike the non-rigid
blimps, costs around 7 million euros ($9 million), but De Beers
has leased this one.

As the airship floats 80 meters (262 ft) above the desert,
the equipment pinpoints rock formations with lower density --
where "kimberlite pipes" with diamonds may be found.

Botswana's most obvious deposits of diamonds, where gems
were thrust close to the surface, have already been uncovered
and De Beers' joint venture with the government -- Debswana --
is under heavy pressure to find new deposits.

"It's a big challenge facing all diamond exploration. We
are now looking to discover the tougher ones," Pitts said.


Existing mines are yielding lower-grade ore with fewer
diamonds, forcing workers to drill deeper. Miners are
increasingly tapping science to help uncover diamonds buried
hundreds of kilometers below the surface.

Miners hunting for elusive diamonds seek traces of the
volcanic rock that forged the gems millions of years ago.

The huge Jwaneng open pit mine, about 200 km (120 miles)
west of the capital Gaborone, was discovered after termites
looking for water brought to the surface mineral grains from
the massive diamond deposit, one of the world's richest.

The zeppelin is part of this process.

The system on board the airship has also been used on small
airplanes, but vibrations caused false readings, while using it
on the ground limits the area covered, Pitts said.

"A ground crew can cover 5 km a day while the airship can
do 250-300 km," he said.

The airship takes off at sunset and flies for six to seven
hours a night because there is less turbulence then.

Before the airship operations started around Jwaneng, De
Beers officials met with chiefs in the surrounding remote areas
to brief them about the strange floating oval in the sky.


The venture could mark a comeback for Germany's Zeppelin
company, founded by Count Ferdinand von Zeppelin eight years
after he flew the first zeppelin airship in 1900.

Zeppelins enjoyed a golden age in the 1930s when they
carried passengers on hundreds of transatlantic flights.

But they fell into disrepute after the spectacular 1937
Hindenburg disaster, when an airship burst into flames in
Lakehurst, New Jersey, killing 35 people on board.

The Zeppelin company lived on, however, and the ZF Group
became a leading supplier of car parts such as chassis.

In 1997, a subsidiary launched New Technology Zeppelins,
which have mainly been used for tourist or promotional flights.

"This (De Beers airship) might mean zeppelins could be used
for other commercial applications," said pilot Fritz Guenther
as he steered the ship above Jwaneng, waving at curious people

Guenther is part of a German team from the Zeppelin company
operating the ship, which is filled with helium and has
propellers on the sides, allowing it to take off vertically
like a helicopter.

Bostwana is De Beers' key producer, providing 32 million
carats of diamonds last year, two-thirds of the total for the
company which is 45 percent owned by mining group Anglo

De Beers -- which controls around half the world's diamond
supply -- is scrambling to find new mines after a European
Union anti-monopoly deal that will force it to stop
distributing rough diamonds from Russia's Alrosa from 2009.

Besides spending around $8.5 million on airship exploration
this year, De Beers is also using equipment that measures the
ground for magnetic forces and electrical conductivity to
unearth new deposits.

After pouring over the data, it sends out ground teams to
drill down under the desert sands. Finding a concealed volcanic
"kimberlite pipe," though, is no guarantee of success.

Only one in 10 kimberlites typically contain diamonds.

Pitts says the zeppelin has technically proved itself
during a few months of test flights, surveying ground over
which geological data had already been collected by other

But when asked whether the project had resulted in any big
discoveries, he chuckled. "If I told you, I'd have to shoot