Tuesday, May 22, 2012

Canada man 'swallowed $20,000 diamond'

A man suspected of swallowing a $20,000 (£12,600) diamond is being held in custody in Windsor, Canada, until it passes through his system, police say.

Richard Matthews allegedly swapped the gem for a fake and ate the real one.The incident occurred almost a week ago but the stone has not appeared despite numerous visits to the bathroom.Mr Matthews, 52, was initially being fed fibre-rich foods, but is now eating whatever he wants in order to speed the process, Sgt Brett Corey said.

An X-ray revealed a pair of artificial diamonds, known as cubic zirconiums, in Mr Matthews' intestines. But the translucent quality of the real diamond means it does not appear in screening.The suspect is eager to get the ordeal over with, Sgt Corey added, and is co-operating with police.

The 1.7 carat jewel was taken from Precision Jewellers in the Canadian province of Ontario.Mr Matthews has been charged with theft and breach of court conditions. He is also wanted on warrants in Toronto.

Sunday, May 13, 2012

Pearl earrings left in drawer since 1970s fetch £1.6m at auction

A pair of pearl earrings that were kept in the back of a desk drawer in Wiltshire for 35 years because the owner did not like them have fetched £1.6m at auction.

The jewellery was a gift from a Romanian king to his mistress, who left the pearls to a British friend on her death in 1977. She had no idea of their worth and consigned them to the drawer as they struck her as too big and ostentatious to wear. They were inherited by her nephew, who casually showed them to an auctioneer when he was selling some other items.

Their emergence has generated huge interest from collectors around the world and their worth in the catalogue was estimated at £80,000-£120,000. Following frenetic bidding at the Woolley and Wallis sale-rooms in Salisbury, Wiltshire, on Thursday, the earrings easily broke the £1m mark, snapped up by a private collector who wished to remain anonymous. The market for such jewellery has boomed in recent years because of interest from China and the Middle East.

Jonathan Edwards, of Woolley and Wallis, said: "The bidding just went berserk. The chap who bought them just would not stop. He wouldn't give up and was very determined to get them. It is a hell of a price.

"The couple who sold the earrings were hanging around at the back of the room. They couldn't believe how much they went for. There were absolutely thrilled and had big smiles at the end of the sale. It is an awful lot of money for them."

Edwards said the couple had turned up with a few bits and pieces to sell, then mentioned the pearls almost as an afterthought. "They had been kept in a box in a desk drawer since the late 70s. The man's auntie never liked them. The couple had no idea of their value and never gave them a second thought. They were blown away when I told them the estimate."

Edwards said King Carol II of Romania had bought the pearls for his mistress, Elena. Carol renounced his claim to the throne in 1925 in the wake of the scandal following the romance and he and Elena lived in exile in Portugal. After Elena's death some of her jewellery was left to a British friend she knew in Portugal. The unnamed woman brought them back to Wiltshire but consigned them to the drawer.

The pearls have been examined by the Swiss Gemmological Institute, which called them a "very exceptional treasure".

Friday, May 11, 2012

Goldman Sachs upgrades Petra Diamonds to 'buy'

Petra Diamonds (LON:PDL) was upgraded by one notch to ‘buy’ by Goldman Sachs, which said shares in the FTSE 250 diamond group underperformed over the past five weeks.“We believe this is unwarranted given growth plans remain on result, we upgrade the stock to a buy,” the investment bank said in a note today.

While Goldman upgraded the stock, Northland Capital reduced its target price for Petra due to a decline in grades and increase in costs in the third quarter.However, the broker upheld its ‘buy’ recommendation on the stock, saying that Petra’s investment plans and ramp-up of production at the Finsch mine in South Africa offers shareholders increased returned from a medium risk capex.

The new target of 185 pence, donw from 200 pence previously, still represents a substantial premium to the current share price of 150 pence, which gives it a market cap of nearly £800 million.In its third quarter report, Petra revealed that production jumped 126 percent to 622,509 carats, while revenues rose US$98 million compared with the revenues of US$101.4 million posted for the entire first half of 2012.

While production from Finsch was ahead of expectations at 343,051 carats, grades at the Cullinan mine slipped to 31.5 carats per hundred tonnes (cpht) from 34.8 cpht in the first half, which was partly offset by an increase in tonnes.

In addition, output from other operations undershot forecasts.Northland analyst Ryan Long still expects Petra to hit its full year production target of 2.2 million carats, however, he said lower rough diamond prices are likely to reduce revenues.“The Finsch Mine was a sparkling performer compared to a group of assets that underperformed,” said Long.

“We continue to believe in the ability of Petra’s management and the quality of the assets despite the setbacks encountered in 2012.”

Monday, May 7, 2012

Researchers Use Diamonds to Boost Computer Memory

A team led by Johns Hopkins engineers has discovered some previously unknown properties of a common memory material, paving the way for development of new forms of memory drives, movie discs and computer systems that retain data more quickly, last longer and allow far more capacity than current data storage media.

The research focused on an inexpensive phase-change memory alloy composed of germanium, antimony and tellurium, called GST for short. The material is already used in rewritable optical media, including CD-RW and DVD-RW discs. But by using diamond-tipped tools to apply pressure to the materials, the Johns Hopkins-led team uncovered new electrical resistance characteristics that could make GST even more useful to the computer and electronics industries.

"This phase-change memory is more stable than the material used in the current flash drives. It works 100 times faster and is rewritable about 100,000 times," said the study's lead author, Ming Xu, a doctoral student in the Department of Materials Science and Engineering in Johns Hopkins' Whiting School of Engineering. "Within about five years, it could also be used to replace hard drives in computers and give them more memory."
GST is called a phase-change material because, when exposed to heat, areas of GST can change from an amorphous state, in which the atoms lack an ordered arrangement, to a crystalline state, in which the atoms are neatly lined up in a long-range order. In its amorphous state, GST is more resistant to electric current. In its crystalline state, it is less resistant. The two phases also reflect light differently, allowing the surface of a DVD to be read by A tiny laser. The two states correspond to one and zero, the language of computers.
Although this phase-change material has been used for at least two decades, the precise mechanics of this switch from one state to another have remained something of a mystery because it happens so quickly -- in nanoseconds -- when the material is heated.

To solve this mystery, Xu and his team used another method to trigger the change more gradually. The researchers used two diamond tips to compress the material. They employed a process called X-ray diffraction and a computer simulation to document what was happening to the material at the atomic level. The researchers found that they could "tune" the electrical resistivity of the material during the time between its change from amorphous to crystalline form.

"Instead of going from black to white, it's like finding shades or a shade of gray in between," said Xu's doctoral adviser, En Ma, a professor of materials science and engineering, and a co-author of the PNAS paper. "By having a wide range of resistance, you can have a lot more control. If you have multiple states, you can store a lot more data."

Thursday, May 3, 2012

'Mirror Diamond' necklace yours for $24.4m

A "Mirror Diamond" necklace bearing five Mughal empire pendant diamonds with emerald drops has been offered for private sale at a price of US$20 million (NZ$24.4m), auction house Bonham's has revealed.

It said the Mughal Mirror Diamond necklace was an extraordinary example of the colourless, rough diamonds discovered in the ancient Golconda mines in India during the height of the Mughal empire across the Indian Subcontinent in the 16th and 17th centuries, which were reserved for royalty.

At 28 carats, the central stone is the largest mirror or table-cut diamond known to survive, and the five diamonds (ranging from 16 to 28 carats) are the largest known matching set of table-cut diamonds from the Mughal 17th century. It is most likely that the diamonds belonged to a Mughal emperor.

"The presentation of the Mughal Mirror Diamond necklace, containing five extraordinarily well matched mirror diamonds, is causing great excitement in the world of jewellery scholars as well as potential buyers," Bonhams CEO and International Head of Jewellery Matthew Girling said in a statement.

To both Mughal emperors and Indian maharajas, the quality and size of the gem were of paramount importance, and table-cut diamonds were valued for their clarity and size above all else.

At the time, gem-cutters only sought to remove areas with cracks and inclusions, so the shape of the rough gem determined the final outline of the polished stone. As a result, gems had an irregular and asymmetrical form as the cutter was striving for the maximum size possible.

Weighing approximately 96 carats in total, the skilfully rendered table-cut diamonds were designed to emphasise the beauty of the stones without sacrificing their size.

The table-cut description refers to a thin diamond section with a flat top and bottom, where the diamonds have also been faceted around the edge. This faceting acts as a border around the irregular shape of the diamond, to produce a refractive brilliance.

The GIA (Gemological Institute of America) has speculated that the five near colourless diamonds were cut from the same crystal.The Columbian emerald drops were added at a later date, probably late 18th/early 19th century.

Pendants such as the necklace were an important element of Mughal jewellery and were used as turban ornaments and armbands.

Many of India's royal pieces of jewellery were subjected to the 19th and early 20th century fashion for replacing and recycling old jewels with new, Western settings or re-cutting into brilliant diamonds. And as the Mughal Empire weakened and collapsed, many of the royal jewel collections were dissipated or lost.