Engineering The Return of Bolivian Ametrine

The Anahí Mine nestles in the heart of Bolivia’s rain forest. As the world’s only ametrine mine, and the world’s only quantity producer of large amethyst, you might think it would have iron-fisted control over the supply and prices for the gems. But low prices worldwide for ametrine, amethyst and citrine suggest otherwise.

The mine’s owner, Ramiro Rivero, and his group, Minerales y Metales del Oriente, say they have a plan to spur retailers’ and manufacturers’ interest in amethyst, ametrine and citrine. Rivero says tighter control over supply and the introduction of a line of new products forms part of his company’s new strategy. These include imaginative faceting techniques in calibrated sizes, all executed on a line of gemstones new to the mine – including deep yellow citrine and pale lavender amethyst – that he thinks will find its way into jewelers’ hearts.

Anahí’s challenge

Hundreds of multicolored butterflies flit over a puddle in the Bolivian rain forest near the mine. In the middle of this flapping mass of flying color, a chunk of “Bolivianita,” or ametrine, Bolivia’s de facto national gemstone, is lodged in the mud; a wider glance reveals many surplus chunks of amethyst and citrine lie everywhere. Inside the mine, production continues at a hectic pace as workers dislodge quartzes of varied qualities that line the walls. Last year alone, 540 tons of quartz were mined, 1.2% of it gem grade.

It’s been a while since gem dealers have flitted like the butterflies over ametrine, amethyst or citrine. Rivero acknowledges that times are tough for gemstones that paradoxically have all of the qualifications to be best-sellers. Looking at the gems Anahí produces, it’s hard to believe they aren’t. But Rivero says a multitude of factors have contributed to the decline, factors he’s committed to reversing.

The Brazilians have long controlled market supply of Bolivian quartz. Back when the quartz mines were administered by the Bolivian military dictatorship (in the late 1980s) mine production – regardless of quality – was sold to the only known gem processing marketplace in South America: Brazil.

Because of limited knowledge of the gemstone market, the majority of the production was sold at commercial-grade prices. Even the small percentage of the finest grades of amethyst, ametrine and citrine was sold through this market at rock-bottom prices. Rivero says several tons of the material were sold and continued to be sold even after Minerales y Metales del Oriente bought the mine and assumed control in 1990. “We didn’t have much knowledge of the gem market then,” he admits, “but now we know much more.”

The abundance of supply, particularly inexpensive goods from Brazilian dealers, caused prices to drop. Rivero says he recognizes the folly of pre-vious efforts. “We don’t want any socio-economic group controlling our production any more,” he says. As a solution, Minerales y Metales del Oriente has taken over all processing of its mine run, a job previously farmed out to Brazilians. John Sparks, Minerales y Metales del Oriente’s production manager, says the meticulous job of hammering (cobbing) the rough must be done in-house to realize a consistent product and a workable profit.

Once the processed material has been sorted and classified, production is sold in myriad ways: by the bagful, as sawn material, preformed gemstones, calibrated preformed gemstones and premium-cut gemstones. “Our gemstones must feature world-class cutting standards,” says Rivero. “We would rather not cut at all if we cannot create the best possible cuts for our stones.” Clearly, Rivero believes the key to stabilizing – and indeed re-establishing – credibility for amethyst, ametrine and citrine is to better control the grades of material that are sold, particularly the finest of goods. He sees it as vertical integration: from the mine to the faceted gemstone, all available through his Santa Cruz de la Sierra office.


Another factor affecting Bolivian quartz in the long term is simple availability. Where mining was once close to the surface and the material easier to extract, times have changed. “Every year we have to go deeper and deeper,” says Sparks. “This means greater expense and a smaller production.” Production in 1996 was down 10%-12% from 1995 for this reason. Sparks recounts the history of a famous quartz mine in Brazil. “Everyone thought Maraba would last forever,” he says. “Well, maybe 15-20 years is forever in an uncontrolled gem mine.” Sparks points out that the flow of Brazilian material, including ametrine, is slowing down. Sparks and Rivero believe there has never been a better time to control market supplies. “We want customers to come directly to our offices in Santa Cruz,” Rivero says. (Santa Cruz de la Sierra is Bolivia’s second largest and fastest-growing city and is accessible through major airlines.) “Gemologically, we are a bit isolated here in Bolivia, but we are growing in importance in the gem market.”


Rivero admits that while Bolivia is not a gemstone mecca like Brazil, which boasts numerable gem species and varieties, he’s convinced Bolivia will become a magnet for people who want to avoid the synthetic gem materials that have flooded the market in recent years. “People who come here can be confident of getting a top-quality natural gemstone,” he says.

Most of the synthetics originate in Russia, China, Korea and Japan and are sold in major markets such as Thailand and Brazil (see “Cheap Synthetics Sold as Natural Gems,” September 1996, p. 84).

The quantities of inexpensive synthetic quartz in major markets has pushed down prices because distinctions between natural and synthetic are so difficult (and costly) to achieve – particularly on a mass-testing basis.

AIGS Laboratory in Bangkok, Thailand, has developed inexpensive mass-testing techniques for quartz. But some observers say the extremely low prices for amethyst (in some cases under $1 per carat for commercial goods) will preclude testing at many levels.

“The effect of synthetics has been noticeable,” says Richard Drucker of The Guide, published by Gemworld International Inc. Northbrook, Ill. “Due to the ‘salting’ of natural parcels with synthetics, there has been a drop in demand and a 10% drop in prices for amethyst, especially in the 1-ct. to 5-ct. range.”

Rivero says he has taken measures to combat the problems that can accompany synthetics. “We sell only to partners with an excellent reputation,” he says. “We are concerned because we have a vested interest in the future of our product. Jewelers must be able to assure their clients that what they are selling is natural.”

The company also may require contractual agreements giving it the right to batch-test its own customers’ inventory at random to check for synthetics. Rivero says the proposal was floated to a few vendors and received mixed reviews. But he sees little alternative. The synthetics threat has affected his main product (amethyst accounts for about 30% of mine variety output) and has even had detrimental side effects on the sale of ametrine and citrine. (Note: synthetic citrine is also a problem, though not as substantial as that of amethyst. Synthetic ametrine has been reported in Russia, but because of distinct visible differences with the natural material, it’s not a major threat, at this time.)


Falling prices overall have meant shrinking margins for purveyors of amethyst and other quartzes at many levels. This factor, say some observers, has had unintended consequences further undermining amethyst marketability.

The most important consequence of shrinking profit margins: budgeting for promotion of amethyst, ametrine and citrine becomes cost prohibitive, says Dana Schorr of Schorr Marketing and Sales in Santa Barbara, Cal. Then fewer consumers learn about quartz or see it as an available option.

For now, says Schorr, Bolivian quartz is still not a profitable market, though he believes it should be. “Minerales y Metales del Oriente has a good product that should be worth a lot more,” he says. “I have long heard their theory about market control, but my experience has been that Brazilians still buy cheaper material than I can from Bolivia. This limits my ability to sell at a profit for the prices I have paid.”

Rivero, who says he no longer supplies material to Schorr, disagrees. “We are clear about controlling our supplies,” he says. As an example, he says volume manufacturers such as QVC that may have gone to Brazil with their orders now come to Minerales y Metales del Oriente. “Brazil can simply not fill that kind of order and we can,” he says. Rivero feels exposure on home shopping networks such as QVC will go a long way in promoting products that Minerales y Metales del Oriente can supply in volume. A recent visit to the Anahí camp by crews from QVC was slated to be aired in October to promote mixed ametrine colors.

Rivero says finer material will still be reserved for jewelers who like to show one-of-a-kind gemstones.

He also says his company’s aim is to work with middlemen who will best represent his product. “We need to give our product the maximum added value, that is to make our whole operation feasible,” he says. “But we want to deal only with those we and the market can trust. Others also get involved in creating [demand]and marketing our materials.”

Anahí’s promise

Of all the quartz produced at Anahí, ametrine is perhaps the most unique, being found in commercial quantities only in Bolivia. It’s relatively plentiful and decidedly beautiful and comes in a variety of sizes. (Ametrine represents 15%-20% of the total cuttable material extracted from his main mine; 5% of that is top quality.)

For those who like color ranges, ametrine is available in a startling array of saturations. Understandably, ametrine has a lot to offer discerning gem lovers around the world. Rivero points out that enthusiasts have responded accordingly: more prizes for gems have been awarded to ametrine over the past few years at the American Gem Trade Association’s Cutting Edge and Spectrum competitions than for any other single gemstone.

Surprisingly, ametrine – which has traditionally been described as a 50-50 amethyst and citrine split – has seen a revolutionary new look described as a “mix of colors.” This is a far better way to conserve yield, Rivero says, because sacrifices don’t have to be made to maintain the 50-50 pure color ratio. The result is a new breed of ametrine jewelry where purple and yellow appear randomly throughout the gemstone, at times blending into a peach-colored mix.

Amethyst is Anahí’s biggest product and competes easily with the more saturated and lightest versions of amethyst from other known sources. Dark colors can resemble the fabled Pau D’Arco material from Brazil with sultry hues and flashes of red. But Rivero is also banking on rosa de francia or rose de France, a trade name for pale lavender amethyst.

A new area produces citrine that Minerales y Metales del Oriente says can be heat-treated to vibrant, saturated yellows. Sparks says none of the quartz extracted from older veins was treatable to these vivid colors.

Rivero also is banking on a new gem color that he feels is quite salable because of dwindling supplies of citrine in major producing countries such as Brazil. A few “bicolor” citrines have been found also, but as with the ametrines, yield is not as good so the gemstones remain more of a novelty than a true commercial item.


There is no direct route to Anahí unless you fly over the Amazonian rain forest in small aircraft and land on the startlingly sudden grassy strip carved out of the jungle. Rivero refuses to fly, having survived a previous air accident in the jungle on his way to the mine. Instead, he takes a route that winds from Puerto Suarez, a drowsy border town, and up the piranha-, mosquito- and alligator-infested Paraguay River. The river, and a huge swamp known as el pantanal is the same trek, in reverse, that the mine’s gemstones take in order to reach dealers and jewelers.

Getting to Anahí is neither an easy way in for miners nor an easy way out for the gemstones. For now, steady supplies of Bolivian quartz continue to float their way down the river and into the marketplace. Backstock supplies and varieties of quartz are still being sold from inventory and prices are close to the lowest they have ever been.

This poses a problem and an opportunity. The problem: gems with low, low prices can be perceived as “cheap” or “not worthy,” even though they may be relatively rare, as in the case of ametrine. Much depends on production control, cutting standards and marketing strategies. The opportunity: bargain prices offer jewelers a chance to be well-represented in a beautiful gem category without much of a sacrifice.

It’s well worth remembering John Sparks’ advice that there is no such thing as a permanently producing mine. For now, Bolivian quartzes have all the necessary attributes to be best-sellers in the colored stone arena. Everything that is, except perceived value. And that notion could change in a heartbeat.