Blue Labyrinth

8

Dr. Finisterre Paden backed away from the X-ray diffraction machine he had been hunched over, only to find himself ricocheting off what appeared to be a pillar of black cloth. He recoiled with a sharp expostulation and found himself staring up at a tall man clad in a black suit, who had somehow materialized behind him and must have been hovering, inches away, as he worked.

“What on earth?” Paden said furiously, his small, portly frame jiggling with affront. “Who let you in here? This is my office!”

The man did not react, and continued gazing down at him with eyes the color of white topaz and a face so finely modeled that it could have been carved by Michelangelo.

“Look here, who are you?” Paden asked, regaining his curatorial equilibrium. “I’m trying to get some work done and I can’t have people barging in!”

“I’m sorry,” said the man in a soothing voice, taking a step back.

“Well, so am I,” said Paden, somewhat mollified. “But this is really an imposition. And where’s your visitor’s badge?”

The man reached into his suit and removed a brown leather wallet.

“That’s no badge!”

The wallet fell open, revealing a dazzle of blue and gold.

“Oh,” said Paden, peering closely. “FBI? Good Lord.”

“The name is Pendergast, Special Agent A. X. L. Pendergast. May I sit down?”

Paden swallowed. “I suppose so.”

With a graceful flourish, the man parked himself in the only chair in the office other than Paden’s and crossed his legs, as if readying himself for a long stay.

“Is this about the murder?” Paden asked breathlessly. “Because I wasn’t even in the Museum when that happened. I don’t know anything about it, never met the victim. On top of that, I’ve no interest in gastropods. In my twenty years here, never been in that hall, not even once. So if that’s what…”

His voice trailed off as the man slowly raised a delicate hand. “It isn’t about the murder. Won’t you sit, Dr. Paden? It is your office, after all.”

Paden took a wary seat at the worktable, folded and unfolded his arms, wondering what this was about, why Museum security hadn’t notified him, and if he should answer questions or perhaps call a lawyer. Except he had no lawyer.

“Really, Dr. Paden, I do ask your forgiveness for the sudden intrusion. I have a small problem I need your help with — informally, of course.”

“I’ll do what I can.”

The man extended one hand, closed. Like a magician, he opened it slowly to reveal a blue stone. Paden, relieved that it was a mere identification problem, took the stone and examined it. “Turquoise,” he said, turning it over. “Tumbled.” He took a loupe off the worktable, placed it in his eye, and looked more closely. “It appears to be natural stone, not stabilized and certainly not reconstituted, oiled, or waxed. A fine, gemmy specimen, of an unusual color and composition. Most unusual, in fact. I’d say it’s worth a fair amount of money, perhaps more than a thousand dollars.”

“What makes it so valuable?”

“Its color. Most turquoise is sky blue, often with a greenish cast. But this stone is an unusually deep, deep blue, almost in the ultraviolet spectrum. That, along with its surrounding golden matrix, is very rare.”

He removed the loupe, held the stone back out to the FBI agent. “I hope I’ve been of assistance.”

“Indeed you have,” came the honeyed return, “but I was hoping you might tell me where it came from.”

Paden took it back, examined it for a longer period of time. “Well, it’s certainly not Iranian. I’d guess it’s American — southwestern. Startling deep-azure color with a golden spiderweb matrix. I would say this most likely comes from Nevada, with Arizona or Colorado as outside possibilities.”

“Dr. Paden, I was told you were one of the world’s foremost experts on turquoise. I can see already that I was not deceived.”

Paden inclined his head. He was surprised to meet someone from law enforcement as insightful, and as gentlemanly, as this fellow.

“But you see, Dr. Paden, I need to know the exact mine it came from.”

As he spoke, the pale FBI agent looked at him most intensely. Paden smoothed his hand over his bald pate. “Well, Mr., ah, Pendergast, that’s a horse of a different color.”

“How so?”

“If I can’t recognize the source mine from an initial visual examination — and in this case I can’t — then testing of the specimen would be required. You see—” and here Paden drew himself up as he launched into his favorite subject—“turquoise is a hydrous phosphate of copper and aluminum, which forms by the percolation of water through a rock with many cavities and empty spaces, usually volcanic. The water carries dissolved copper sulfides and phosphorous, among other things, which precipitate in the interstices as turquoise. Southwestern turquoise almost invariably occurs where copper sulfide deposits are found among potassium feldspar bearing porphyritic intrusives. It can also contain limonite, pyrites, and other iron oxides.” He rose and, moving fast on stubby legs, walked to a massive cabinet, bent over, and pulled open a drawer. “Here you see a small but exquisite collection of turquoise, all from prehistoric mines. We use it to help archaeologists identify the source of prehistoric turquoise artifacts. Come, take a look.”

Paden waved the agent over, then took the turquoise sample from him and rapidly compared it with others in the drawer. “I don’t see anything close to a match here, but turquoise can vary in appearance even from one part of a mine to another. And this is only a small sampling. Take this piece of Cerrillos turquoise, for example, from the Cerrillos mines south of Santa Fe. This rare piece comes from the famed prehistoric site known as Mount Chalchihuitl. It’s ivory with a pale-lime matrix, of great historical value, even if it isn’t the finest quality. And here we have examples of prehistoric turquoise from Nevada—”

“How terribly interesting,” Pendergast said smoothly, stemming the flow of words. “You mentioned testing. What sort of testing would be necessary?”

Paden cleared his throat. It had been mentioned to him more than once that he had a tendency to run on. “What I’ll have to do is analyze your stone — turquoise and matrix — using various means. I’ll start with proton-induced X-ray emission analysis, in which the stone is bombarded with high-speed protons in a vacuum, and the resulting X-ray emission analyzed. Fortunately, here at the Museum we have an excellent mineralogy lab. Would you care to see it?” He beamed at Pendergast.

“No, thank you,” said Pendergast. “But I’m delighted you’re willing to do the work.”

“But of course! This is what I do. Mostly for archaeologists, of course, but for the FBI–I am at your service, Mr. Pendergast.”

“I almost forgot to mention to you my little problem.”

“Which is?”

“I need the work done by noon tomorrow.”

“What? Impossible! It will take weeks. A month, at least!”

A long pause. “But would it be physically possible for you to complete the analysis by tomorrow?”

Paden felt his scalp prickle. He wasn’t sure that this man was quite as pleasant and easygoing as he seemed at first. “Well.” He cleared his throat. “It’s physically possible, I suppose, to get some preliminary results by then, but it would mean working nonstop for the next twenty hours. And even then I might not succeed.”

“Why not?”

“It would all depend on whether this particular type of turquoise has been analyzed before, with its chemical signature recorded in the database. I’ve done quite a lot of turquoise analyses for archaeologists, you see. It helps them figure out trade routes and so forth. But if this piece comes from a newer mine, we might never have analyzed it. The older the mine, the better the chance.”

A silence. “May I ask you, Dr. Paden, to kindly undertake this task?”

Paden smoothed his pate again. “You’re asking me to stay up for the next twenty hours, working on your problem?”

“Yes.”

“I have a wife and children, Mr. Pendergast! Today’s a Sunday — normally I wouldn’t even be here. And I am not a young man.”

The agent seemed to take this in. Then, with a languid motion, he reached into his pocket and removed something, again holding it in his closed hand. He reached out and opened the hand. Inside was nestled a small, glittering reddish-brown cut stone of about a carat. Instinctively, Paden reached out to take it, screwed the loupe into his eye, and examined it, turning it this way and that. “Oh my. Oh my, my. Strongly pleochroic…” He grabbed a small, handheld UV light from the table and switched it on. The stone instantly changed color, becoming a brilliant neon green.

He looked up, his eyes wide. “Painite.”

The FBI agent bowed his head. “I was not deceived in thinking you were a most excellent mineralogist.”

“Where in heaven’s name did you get this?”

“My great-grand-uncle was a collector of oddities, which I inherited along with his house. I plucked this from his collection, as an inducement. It’s yours — provided you accomplish the task at hand.”

“But this stone must be worth… good heavens, I hesitate to even put a price on it. Painite is one of the rarest gemstones on earth!”

“My dear Dr. Paden, the information on what mine that turquoise came from is far more precious to me than that stone. Now: can you do it? And,” he added dryly, “are you sure your wife and children won’t object?”

But Paden was already on his feet, placing the turquoise in a ziplock bag and thinking ahead to the many chemical and mineralogical tests he would need to perform. “Object?” he said over his shoulder as he departed into the inner sanctum of his laboratory. “Who the hell cares?”