A prehistoric mastodon skull from Texas, a 26-pound gold nugget from Mexico, a Chinese meteorite and a fossilized Dominican lizard are among the 419 items featured at this week's Natural History Auction.

Natural History Auction

This prehistoric four-tusk mastadon skull uncovered in a gravel pit in La Grange, Texas, is valued between $120,000 and $160,000.

The auction by Dallas-based Heritage Auction Galleries can't come soon enough for the folks at Mt. Blanco Fossil Museum, in the small West Texas town of Crosbyton.

Selling the mastodon skull they've come to know as Lone Star for upward of $120,000 – its estimated value – could mean a major turnaround for the museum, which is short on funds.

Billed as the largest four-tusk mastodon skull ever found, the skull was uncovered in a gravel pit near La Grange, southeast of Austin, and was sold in 2004 to Joe Taylor, the museum's owner and curator.

Mr. Taylor and a crew of students and volunteers spent more than a year painstakingly preserving and restoring the prehistoric piece, but he says he's more than willing to sell it to support a school of paleontology and teach others the skills he spent a lifetime honing.

"We've got so much time and money into it, we're too far extended," said Mr. Taylor, whose museum can't support any staff.

Potential buyers should be prepared to make room for their new purchase.

"It's almost the size of a Volkswagen," said Kelley Norwine, vice president of marketing for Heritage Auction Galleries.

The La Grange skull is one of many unique finds up for grabs in Sunday's auction. Heritage Auction Galleries' Web site includes the sometimes quirky back stories of sale items that collectors and museums find especially interesting.

Natural History Auction

A 3 1/2-inch lizard preserved in amber for 30 million years is valued at $120,000.

"A lot of times, the story is what makes the item," Ms. Norwine said. "I think it helps to attract attention."

The famed Boot of Cortez, a 26-pound gold deposit, was discovered near Caborca, Mexico, in 1989 by a man using a metal detector he'd bought at RadioShack. The nearly foot-long, boot-shaped nugget is expected to fetch more than $1 million at auction.

Also up for auction is a fossilized lizard that's been perfectly preserved in prehistoric amber for 30 million years. The 3 ½ -inch lizard from the Dominican Republic is the largest intact animal discovered in amber and is valued at about $120,000 – about $30,000 less than a pallasite meteorite found near Fukang, China, in 2000 that's also up for grabs.

Sunday's auction in Dallas will culminate with a live auction, but there are several ways to bid on items: in person, via e-mail, by phone, online or by fax.

In Crosbyton, they've got their fingers crossed that someone will purchase the mastodon skull so the museum can continue its prehistoric pursuits – and they'd like it to be a Texas buyer.

"It would be kind of nice if somebody wanted to acquire it and keep it here in Texas," said Henry Johnson, a retired Los Angeles firefighter who moved to Crosbyton in 2006 and now helps at the museum.

"There's a lot of pride in what we have here in Texas," he said.

What: Natural History Auction

Where: Heritage Auction Galleries Fine Arts Annex, 1518 Slocum St. in the Stemmons Corridor

When: The public can view items at the annex from 10 a.m. to 6 p.m. Thursday, 10 a.m. to 6 p.m. Friday and 10 a.m. to 7:30 p.m. Saturday. The live auction will begin at 1 p.m. Sunday.