Thursday, May 30, 2019

Flawless 'Bubble Gum Pink' Diamond Fetches $7.5 Million at Christie's Hong Kong

An internally flawless bubble gum pink diamond weighing 3.44 carats was the colorful star of Christie's Hong Kong auction on Tuesday as it sold for $7.5 million, or $2.2 million per carat.

The cushion modified brilliant-cut diamond — aptly dubbed "The Bubble Gum Pink" — is set in a ring by luxury jeweler Moussaieff. The fancy vivid purplish-pink diamond is framed by small pear-shaped pink diamonds on the corners and larger marquise-cut white diamonds on the sides.

Celebrated for its superb color, The Bubble Gum Pink was classified by Christie's Chairman Francois Curiel as "probably the strongest pink I have ever seen in my 50-year life of jewelry specialty at Christie’s."

The hammer price for the auction's top lot was on the high end of Christie's pre-sale estimate of $6 million to $8 million.

Other top lots at the Magnificent Jewels event include the following:

• A pair of emerald earrings called The Grand Muzos fetched $4.5 million. The Colombian-sourced emeralds weigh 23.34 carats and 23.18 carats, respectively, and are accented by white diamonds and pearls. Each of the diamonds weighs exactly 3.01 carats and share identical F-color and VS2 clarity gradings. Christie's had estimated the pair would sell in the range of $3.8 million to $6.5 million.

• A necklace featuring 47 jadeite beads ranging in size from 9.8mm to 13.3mm and accented with a ruby and diamond clasp yielded $1.9 million, slightly below the pre-sale estimate of $2 million to $3 million. The necklace measures 22.24 inches (56.5cm) in length.

• An elaborate diamond necklace by Bulgari — highlighted by a rare 1.02-carat vivid green-blue modified brilliant-cut diamond and a modified pear brilliant-cut diamond of 11.69 carats — sold for $1.57 million. The large center diamond is internally flawless. The hammer price was just below the pre-sale estimate, which Christie's set at $1.6 million to $2.3 million.

The Christie's Magnificent Jewels sale in Hong Kong presented more than 260 lots and netted $44.4 million.

Credits: Images courtesy of Christie's.

Wednesday, May 29, 2019

'We're Closer Than Ever to Finding the Mother Lode' at Lulo Mine: Lucapa Chairman

The chairman of Lucapa Diamond Company told stockholders Monday that his exploration team is closer than ever to striking the mother lode at the flagship Lulo site in Angola.

While Lulo already has a reputation for turning out large, high-quality diamonds at its alluvial deposit, chairman Miles Kennedy believes the prospect of "huge wealth" is well within reach.

“There are no silver bullets in the kimberlite exploration game...” Kennedy said. “But the patient and methodical approach adopted by our exploration team is narrowing down and confining the search areas of our quest. It may take us another couple of years, but I am more confident than ever that we can indeed find the diamond source at Lulo.”

“And while kimberlite exploration can by nature be painstakingly slow," he added, "I am equally of the view that we are closer than ever to finding the mother lode...”

The Lulo mining area, which comprises 1,100 square miles along the length of the 31-mile Cacuilo River, has already generated a series of high-quality, impressive finds. The largest to date was discovered in 2016 and named "4 de Fevereiro." The 404.20-carat rough gem was eventually sold for $16 million to luxury jeweler De Grisogono, which cut it into a flawless 163.41-carat emerald-cut diamond.

To identify and protect sizable diamonds that might otherwise be damaged in the sorting process, Lucapa installed a $3.5 million state-of-the-art XRT large-diamond recovery system in 2017. The system uses advanced X-ray transmission technology (XRT) and larger screens (55mm) so diamonds up to 1,100 carats can be cherry picked. XRT technology is also more efficient at recovering low-luminescing, ultra-pure Type IIa diamonds. Diamonds from the Lulo site typically sell for $2,000 per carat.

Lucapa has a 40% stake in the Lulo mine and holds an exploration license that runs until April 2023. The mining firm maintains two partners in the project — Empresa Nacional de Diamantes EP and Rosas & Petales.

Credits: Rough diamond images courtesy of Lucapa Diamond Company. Emerald-cut "4 de Fevereiro" image via PRNewsfoto/de GRISOGONO.

Tuesday, May 28, 2019

Gold-Loving Fungus Is the Latest in a Series of Low-Impact Exploration Tools

A fluffy pink fungus that thrives on gold is the latest in a series of low-impact exploration tools available to Australian miners.

Geologists from Australia’s national science agency, CSIRO, reported that a thread-like fungus found 130 km southeast of Perth, has the ability to draw gold from the soil. What's special about the fungus, called Fusarium oxysporum, is that it uses a special chemical to dissolve the gold and another chemical to turn it back to a solid in the form of tiny nanoparticles.

A microscopic view of the fungus shows how its strands are coated in gold.

The presence of gold-rich fungi on the surface could provide valuable clues about new deposits underground. The geologists at CSIRO believe the fungi could provide a cost-effective way to find gold while reducing the impact on the environment.

Australia is the world's second largest gold producer, and while gold production reached all-time highs in 2018, forecasts show that production will decline in the near future unless new gold deposits are found.

And nature seems to be providing valuable new ways to support exploration without harming the environment.

Less than a month ago, we reported how leaves from the gum tree are helping miners pinpoint high-yield gold deposits in South Australia. Other Aussie miners are studying termites that harbor gold in their mounds. These tiny traces of gold can be linked to bigger deposits below the surface.

When comparing the fungi, CSIRO geologists noted the specimens with the most gold on their strands seemed to enjoy a biological advantage. They had the ability to grow larger and spread faster than those that didn’t interact with gold.

The geologists were surprised by the fungi's ability to synthesize gold.

"Fungi are well-known for playing an essential role in the degradation and recycling of organic material, such as leaves and bark, as well as for the cycling of other metals, including aluminium, iron, manganese and calcium," noted CSIRO lead author Dr. Tsing Bohu. "But gold is so chemically inactive that this interaction is both unusual and surprising – it had to be seen to be believed."

In the future, this gold-loving fungus might be employed not only to help pinpoint new gold deposits, but also to extract gold from sewage sludge and e-waste, such as discarded electronics.

The CSIRO gold-loving fungus findings were published in Nature Communications. The discovery was made possible thanks to collaboration among CSIRO, the University of Western Australia, Murdoch University and Curtin University.

Credit: Image courtesy of