"It's gonna become one of these lost gold mine stories, I guess," said Bob Verish, sounding puzzled but resigned. "Prospector finds something and then loses it."

The potential gold mine in this case is the range of California desert where Verish picked up two curious black rocks a decade or two ago -- rocks that turned out to be some of the rarest material on Earth. They were pieces of Mars ripped from the planet by some cataclysmic impact ages ago and thrown to tumble through space.

The stones gained incredible value when scientists determined last December that they were Martian meteorites. They changed instantly from forgotten scraps salvaged from the rock crates that clutter Verish's back yard into extraterrestrial gems that could now sell for several hundred dollars per gram.

Meteorite hunters and dealers have expressed skepticism at Verish's lack of recall at what could be a patch of desert littered with martian treasure. But Verish said he's been hiking in western deserts for 20 years picking up rocks everywhere he goes.

"There isn't really any secret there," said Verish, who is 52, explaining that he can't remember details of how or when he picked up the two small black rocks. He was new to California in the early 1980s when he started collecting rocks in the desert. "I went to many places not knowing where I was going or where I had been," he said.

Verish works at NASA's Goldstone Tracking Station in the middle of California's Mojave Desert. He implements the latest tracking equipment that NASA uses to keep in touch with its spacecraft. Traveling to and from work, he made countless trips through the desert, where he often stopped to hike and explore. It gave him time to feed his rock-collecting habit.

"I'm just amazed that I'm driving a vehicle with a piece of rock from Mars."
     

Verish has been grabbing rocks from the ground since he was a kid growing up in Pittsburgh, but back east in the Steel Belt, many of the stones he found were pieces of slag scattered about from the smelters. He became an expert at looking at slag, but he always dreamt of going out west and finding rocks in the desert.

When he finally did move to California about 20 years ago, hiking became a common pastime and his fascination with geology grew. So did his collection of rocks.

He saved the rocks he found on his excursions. His collection quickly grew to fill milk crates and wooden boxes in the back yard of his Los Angeles home. It spread to his porch, then to the garage.

His boxes of rocks accumulated this way for years until last year the clutter had become too much. It was a hot summer, so it was easy simple to invoke the heat as an excuse to push off the inevitable task of scouring through his collection to throw most of it out, but in late autumn, Verish had run out of excuses.

"It was kind of a nice cool day. I was going through the big wooden cases of rocks here and there and in the garage too. That's when I came across them."

They were two striking black rocks that Verish said looked glassy on the outside. Both fit comfortably in the palm of his hand. One weighed just over a pound (457 grams), the other, about half that (245 grams).

"I have to tell you it didn't really click in my head immediately. It wasn't until I picked up the second one, and that was an obvious oriented meteorite, that I said 'Oh, where did these come from? What are these doing in here?'" Verish said.

An oriented meteorite is one that is cone shaped, much like the nose of a rocket. Instead of tumbling erratically while falling through the atmosphere, some meteorites are aerodynamically stable so they keep a certain orientation, that is, one face points forward. The shape is refined as the rock burns through the atmosphere. Rough edges are melted and vaporized away by the heat of friction, so that when it lands, the oriented meteorite has a rather smooth conical shape.

Meteorites also often have a fusion crust - a thin charred outer layer created by melting. It was this crust that gave Verish's two meteorites a glassy appearance.

But Verish didn't know any of that when he originally fetched the rocks out of the desert. He speculates that it may have been the meteorites' resemblance to slag that drew his attention to them and may be why he bothered to keep the rocks in the first place. They just didn't fit in the tan desert landscape.

By the time he he cleaned out his collection last autumn, though, he knew much more. He had earned a geology degree from California State University at Los Angeles, and he knew a little about meteories - enought to suspect that he should have an expert look at it.

Verish went to the planetary science department at the University of California at Los Angeles, where he met Alan Rubin, a meteorite expert who examines rocks that people suspect might come from space.

Rubin was not immediately impressed with what Verish brought in, Rubin said. The sample was obviously a volcanic basalt, a type of rock quite common on Earth. "When people bring these in, my first reaction is that it is terrestrial, something we call meteor-wrongs," Rubin said.

But when he examined a slice of the rock under the microscope, he saw a startling amount of a mineral called maskelynite. Maskelynite forms when a common mineral called plagioclase is shocked so heavily that it crystallizes into glass. This only occurs in very strong-impact collisions, like the impacts that occur when giant meteorites slam into planets or when asteroids collide. The more maskelynite found in a rock, the heavier it has been shocked.

Small amounts of maskelynite are found in some lunar meteorites and also in terrestrial basalts where huge meteorites have pounded into Earth sometime in its distant past, Rubin said. But the rock that Verish brought in had maskelynite in abundance. Nearly all the plagioclase had been transformed into maskelynite, indicating that it originated in a very large planetary body. Only large bodies can support the amount of shock necessary to produce abundant maskelynite.

The existence of so much maskelynite suggested heavily that the rock was from Mars. "The only basalts that have abundant maskelynite are martian," Rubin said. Further tests were needed to confirm it, but as far as Verish was concerned, the examination had proven that the rocks were a big deal.

What surprised Verish most was the fact that Rubin and his colleague Paul Warren were so calm.

"You've got to understand, they're so professional man, they're so understated.," Verish said. "[Rubin] would just say what he would see. He would say 'Oh, well that's maskelynite.' And that's tantamount to saying -- well that's huge! You get that when impacts blast crust off of a planet or the moon or whatever."

In the end, Warren and Rubin congratulated each other and Verish for having found it, and Verish left.

"I left there shocked because it was just so surreal," he said. "I was taking the sample back with me and I'm just amazed that I'm driving a vehicle with a piece of rock from Mars."

It was 15 minutes before he realized he was driving alone in a carpool lane at rush hour on an L.A. Freeway.

Shortly afterwards the meteorites were verified to be from Mars, and they became the hottest property in the meteorite business. They were classified and given the names LA001 and LA002. Meteorites are generally named after the place where they are found, but in this case it isn't clear where the meteorites come from, so Verish's back yard in L.A. is being called the discovery site.

In February Verish sold the bulk of LA001 -- the larger of the two pieces -- to two New York meteorite dealers for a price one of the buyers called "well into six figures." They subdivided the sample and made exchanges with several institutions that planned to use the rocks for science and to display.

The whole experience has turned Verish into an ambassador for meteorite education. "I feel like I sort of owe something now to meteorite science and collecting," he said.

The press coverage of his discovery has made a name for him as something of a meteorite expert, and a lot of people now contact Verish if they think they have found a meteorite. So he is focusing a lot of his time on helping people find out whether their finds are meteorites and if they are, then getting those rocks into the hands of people to identify and classify them.

"I feel that I have some responsibility now to pursue that," he said. "I'm just feeling the need to get these recovered before they weather any more out there in the desert."

There's also an off chance that there are still some meteorites weathering in Verish's yard. "I have boxes of rocks yet to go through. I my retirement years maybe I'll do that," he said.