Global diamond connoisseurs competed for 65 "Signature" gems
from the Argyle Pink Tender of 2007

By Robert Weldon

A group of diamonds from the 2007 Argyle Pink Tender included (from top): 1.74-ct. Fancy purplish-red; 0.77-ct. Fancy dark gray-violet; 1.22-ct. Fancy vivid purplish-pink; 0.69-ct. Fancy purplish-red. Each of the tender’s 65 stones came with reports from GIA and AGT laboratories. Only two gems from the collection were cut as round brilliants. Photo by Robert Weldon

Despite this trickle of fancy pinks and reds into the marketplace, Argyle produces the lion's share, about 90 percent of global production, experts say. These diamonds are sold through a yearly tender, or offering, in which carefully selected and qualified global buyers make secret, sealed bids on the diamonds of their choosing. The 2007 tender was held in three cities: New York City, Perth (Australia) and Hong Kong, and attracted approximately 80 of the world's most discerning buyers.

Prices for rare pink and red diamonds have been rising steadily since the tenders were first started in 1984, perhaps because the mine producing them has been predicted to close by 2018. In fact, all of the 2007 gems sold out.

"This year the diamonds received an unprecedented level of interest," remarks Jean-Marc Lieberherr, Rio Tinto's Sales and Marketing general manager. "Competition was fierce."

While Rio Tinto doesn't reveal who the buyers are, or what the winning bids might be, buyers know market prices as they submit their bids. Rio Tinto officials, however, are circumspect about sharing the value of winning bids.

"In addition to commercial sensitivity, it is near impossible to generalize, as the product is not homogenous," explains Robyn Ellison, the company's Communications manager. "Pinks that are tender-caliber are really unique. We can say that price growth has been extremely strong – and in some categories – exponential."

For buyers, a focus on price is understandable since these gems command per carat prices that are often 20-fold that of equivalently sized colorless diamonds.

Expert Eyes
One such buyer is Alan Bronstein, of Aurora Gems Inc. based in New York City, and a renowned fancy diamond expert and collector. Bronstein is not shy about sharing his enthusiasm for the process of viewing Argyle tenders.

"We are so privileged to even see these gems up close. You cannot do so without feeling emotion, especially knowing that in another decade Argyle will cease production."

Bronstein, who has been buying at tenders for more than two decades, says there is not one "best" way to prepare for it. "I look at images of each gem posted on Argyle's Web site ahead of the tender. Each gem has a lot number, so I'll make a note about stones I want to examine more closely. When you finally enter the hotel room [where the tender is being held] your heart beats strongly and you just can't keep your eyes off of the diamonds. You are drawn in. It is a magical experience," he says.

Even more nerve-racking is the anticipation that follows until Rio Tinto's bid deadline is over. "You know you are competing with people who want the same diamond you want – for different reasons. A buzz starts. Some buyers are collectors; others are designers or major jewelers who have a customer in mind. Everyone has to stretch the limits of their budgets."

Bronstein said he did not "win" any of his bids this time.

"I don't have to compete as hard since many important Argyle gems are already represented in the Aurora collection," he says. But it is hard for him not to be wistful: "I remember details of so many of these stones."

Bronstein quintessentially expresses why so many dealers like him have become addicted to Argyle's pinks: "When I see the tender I am like a kid in a candy store. But my favorite gem is not always the darkest or most vibrant. I go for the diamond expressing the most love."