DALLAS (AP) – In the bowels of the Museum of Nature & Science in Fair Park, Tommy Diamond sat hunched over what looked like a huge boulder of plaster.

Yes, there was a lot of plaster there, but what was underneath was much more valuable priceless, in fact.

Diamond spends eight hours (or more) a day chipping away at the vertebra of an Alamosaurus.

Ten vertebrae of the 65-million-year-old dinosaur, uncovered in 1997, are being prepared to go on display for the opening of the Perot Museum of Nature & Science in Victory Park in 2012.

“No one’s ever seen the neck of an Alamosaurus before,” said Tony Fiorillo, curator of earth sciences at the museum. “They’re not the biggest vertebrae ever found, but they’re certainly the biggest ever excavated in Texas.”

The cervical bones were found in Big Bend National Park in West Texas by accident. Fiorillo’s team was working about 500 feet away when University of Texas at Dallas student Dana Biasatti saw the dinosaur’s hip bones poking right above the surface.

They weren’t lifted out of the park until 2001, after extended negotiations with Big Bend officials. Because the vertebrae were so heavy (ranging from 100 to 800 pounds), some had to be airlifted out of the park by helicopter.

Now they sit in the museum’s basement in plaster casts, waiting to be uncovered by the museum’s fossil preparators. It takes six to seven months to chip away at all the plaster and uncover the bone (without damaging it) and get it museum ready.

“When you get past all the dirt and down to the bone, that’s when you get really sucked into it,” said Ron Tykoski, chief fossil preparator. “It gets really exciting, every little layer you peel away.”

The first Alamosaurus bones were discovered in 1922 in New Mexico. Contrary to one’s first thought, the dinosaur was not named after the San Antonio landmark, but rather the river bed where the fossils were found.

The dinosaur is classified as a sauropod, which includes some of the largest animals to live on land. The Alamosaurus, a herbivore, is estimated to have weighed 35 tons.

The Museum of Nature & Science is working with the Smithsonian Institution in Washington, D.C., and UTD, both of which have other parts of the dinosaur. The actual bones will be scanned and casts will be made and put on display in the museum. The real bones are too heavy to use in the full skeleton re-creation.

Three institutions working together on one animal is atypical, Fiorillo said. Usually one organization handles all of the preparation and set up for a museum display. Because the other institutions discovered the other bones decades ago, the three must work together to re-create the entire animal.

But there is one part of the Alamosaurus no one has ever seen — a skull.

“We were really excited because the neck was all articulated,” Fiorillo said. “It was going and going and we were hoping for a skull, but it stopped after the neck.”

Tools that wouldn’t look out of place in a dentist’s office are used to painstakingly chip away slivers of dirt of and plaster. Tykoski and Diamond said it’s not uncommon for their fingers to be numb after consecutive hours of scraping away at the bone.

The museum has two people dedicated solely to getting the Alamosaurus fossils ready. But volunteers have also played a huge part in preparing the bones.

Whittling away at the layers of plaster and dirt for hours on end doesn’t demand expert skill, but it does require quite a bit of patience.

Fiorillo said the volunteers come in when they can, working for a few hours at a time. They come from scientific and nonscientific backgrounds — from anthropology students to fossil enthusiasts to artists.

Marcie Keller, who started full time with the museum at the beginning of October, was an art major in college. She has no experience in archaeology or science at all, for that matter.

Fiorillo said those with an artistic background are some of their best volunteers, because of their good hand-eye coordination.

Keller agreed, adding: “I did a lot of etching and printmaking so this is pretty much doing the same thing. I felt very comfortable in the lab right away.”

The work is tedious, the fossil preparators admit, but there is almost always a huge payoff once the final layer of dirt is scraped away.

“You can be the first person in the world to see a particular bone or fossil,” Tykoski said. “It can look like a big chunk of rock, but maybe you’ll find something under all those layers.

“It’s quite the adrenaline rush.”

(Copyright 2010 by The Associated Press. All Rights Reserved.)