The world's richest diamond owners

We've all heard of the song "Diamonds Are a Girl's Best Friend," but it seems diamonds are also becoming an investor's best friend.

Rough diamond prices have jumped nearly a third since 2005 and are likely to rise another 20 percent by 2017, bolstered by demand in Asian economic powerhouses China and India, according to wealth research firm Wealth-X.

Record prices of these baubles have been making headlines lately. A pear-shaped 101.73 carat "flawless" diamond, for example, sold for a record $27 million to luxury jeweler Harry Winston at a Christie's auction in Geneva.

It's no surprise that many investors want in on the action.

According to net worth data provided by Wealth-X, as of July 15, 2013, the world's richest diamond owners consist of collectors, dealers, business owners as well as investors who have stakes in some of the world's biggest diamond mines.

Some of the individuals on our list are also known to own some of the rarest and most expensive diamonds ever found.

So, who are the world's top 10 billionaire diamond owners? Click ahead to find out.

Posted: July 25, 2013
By Rajeshni Naidu-Ghelani

Net worth: $1 billion

Kicking off our top 10 list of the world's richest diamond owners is Robert Mouawad, who bought a 101.84 carat diamond at auction house Sotheby's for $12.76 million in 1990.

The 11-sided mixed cut diamond known as "the Mouawad Splendor" (pictured) made it into the Guinness Book of World Records as the world's most expensive single pear-shaped diamond at that time. Robert Mouawad is a third generation member of the Lebanese Mouawad family, who has been involved in the jewelry business since the 1890s. The family owns the Geneva, Switzerland-based jewelry company Mouawad. When Robert was the firm's president, he expanded the business from Saudi Arabia to Europe, Asia and North America and set up Geneva as the jeweler's new base in the early 1970s.

Robert Mouawad's other famous diamond purchases include the 135.92 carat Queen of Holland diamond in 1978, which was once the largest cut diamond in the world and the 68.09 carat Taylor Burton diamond, made famous by actor Richard Burton when he purchased it for his actress wife Elizabeth Taylor in 1969. Mouawad bought the diamond in 1979 after it was sold to New York jeweler Henry Lambert for $5 million.

Net worth: $1.1 billion

Fred Mouawad is one of the three current co-guardians of the Geneva-based family jewelry business Mouawad.

Mouawad is a fourth-generation member of the Lebanese family, which have been involved in the jewelry business since the 1890s. He heads the diamond division of the company and has also founded the Syneria One group of companies, which is involved in industries from jewelry retailing to food outlets.

Mouawad garnered attention last November when he was the last person to bid for a 76.02 carat diamond, which once belonged to Archduke Joseph August of Austria, before it sold for a record $21.48 million in a Christie's auction to an anonymous buyer, Reuters reported.

Net worth: $1.1 billion

Jorg Bucherer is the chairman of Swiss family run jewelry business Bucherer Group.

Bucherer was founded by Jorg's grandfather Carl-Friedrich Bucherer in 1888 with its first watch and jewelry store in Lucerne, Switzerland. The group now has around 1,500 employees and about 26 stores across Europe, including what it calls the world's largest watch and jewelry store in Paris (pictured). The jeweler's range currently consists of a whopping 50,000 items.

Burcherer launched the Lacrima diamond collection in 2007 to target the top end of the market. The line of 25 diamond set pieces includes rings, necklaces and earrings - which now also includes a basic, premium and deluxe series. Some of the most notable diamond pieces crafted by Bucherer include the Valse Des Cristaux - a necklace, pendent and earring set that has more than 36 carats of diamonds, the Nature en Eveil necklace with 24.79 carats of diamonds and the Reine Blanche necklace, which has 44.97 carats of brilliant diamonds.

Net worth: $1.4 billion

Lev Leviev is an Uzbekistan-born Israeli business tycoon involved in the trading and mining of diamonds in Russia and African countries, which are home to some of the world's largest diamond mines.

Leviev, known as the "king of diamonds," made headlines last year in a court battle with his one-time partner Arkady Gaydamak who was seeking hundreds of millions of dollars in unpaid commissions from Angola's mines. Leviev's assets in Angola include a stake in the Catoca diamond mine, which is one of the world's largest, Reuters reported.

Apart from owning luxury jewelry stores in global cities like London, Leviev is also the chairman of investment firm Africa Israel Investments (AFI) Group, which is involved in industries like real estate, construction, and tourism.

The former wife of American mogul Donald Trump, Ivana Trump wore 450 carats of diamonds from Leviev's jewelry collection at her wedding celebrations in 2008, which included a 140 carat yellow diamond set at a pre-wedding party, according the jeweler.

Net worth: $1.7 billion

Georges Nicolas Hayek Jr. is the CEO of Switzerland's Swatch Group, which bought the high-end jewelry arm of Canadian firm Harry Winston for $1 billion in January.

The move gave Swatch, the world's biggest watchmaker by sales, one of the marquee jewelry luxury brands worn by the likes of Hollywood elites Marilyn Monroe and Elizabeth Taylor. Every year, Harry Winston lends out millions of dollars' worth of jewels to be worn by movie stars for famous televised events like the Oscars, while Swatch is the world's largest consumer of polished diamonds. Hayek is the son of Lebanese Nicolas George Hayek, who co-founded the Swatch Group in 1983.

One of the famous diamonds that Hayek has acquired through the Harry Winston brand recently is what industry watchers have described as a "flawless" 101.73 carat diamond (pictured), which sold for a record $26.7 million at a Christie's auction in Geneva in May. Harry Winston has named the diamond "Winston Legacy."

Net worth: $2.1 billion

British jeweler Laurence Graff is the founder of Graff Diamonds, famous for its giant and rare gems.

Graff began his career as a humble jewelry apprentice at the tender age of 15. After a few failed stints at other jewelry stores, he started designing and selling his own designs independently. By 1960, he founded the luxury brand which today has 35 boutiques around the world. Last year in May, the company made headlines after it pulled a planned $1 billion initial public offering, which was set to be the biggest IPO of the year on the Hong Kong stock exchange, due to volatile market conditions.

Some of the most famous diamonds owned by Graff include the rare Graff Pink diamond (pictured) at 24.78 carats, which the billionaire purchased for $46 million in 2010. Graff also owns the Lesotho Promise, a 603 carat diamond found in a mine in the South African country, which he purchased for $12.4 million in 2006. The company valued a necklace made from 26 stones cut from the Lesotho Promise at more than $60 million in 2011, the New York Times reported.

Net worth: $2.1 billion

Anne-Marie Graff is the wife of British billionaire jeweler Laurence Graff and a shareholder in his company Graff Diamonds.

The Graffs, who have been married for over 47 years, made headlines last year after it was reported that Laurence Graff had fathered a child with a former employee 34 years younger than him, leading Anne-Marie to file for divorce. The divorce, which could have been Britain's biggest divorce settlement, hasn't happened as the couple appears to have reconciled.

In an initial public offering prospectus last year, it was revealed that the couple held a combined total of 645 million shares in Graff Diamonds including those held in trust for their three children. At a maximum offering, the stock would be worth about $3.1 billion, Forbes reported. The company did, however, pull its IPO from the Hong Kong Stock Exchange due to volatile market conditions.

Net worth: $2.6 billion

Dan Gertler is an Israeli businessman, who made his fortune by investing in the Democratic Republic of Congo's (DRC) diamond and copper mines. At 39, he is the youngest person to make the list of the world's richest diamond owners.

Gertler is the founder and president of the Dan Gertler International Group (DGI) and heads his family's Gibraltar registered business - the Fleurette Group. Arriving in Congo in 1997, the billionaire took his family's fortune in diamonds and invested it in mining assets in the DRC, Forbes reported. He has become an influential figure in Congo's mining sector with close ties to the Kinshasa government. His Fleurette Group and its partners employ around 20,000 local workers, Reuters reported.

Wealth and investment have also come with controversy for Gertler, who has been accused of being involved in deals that have benefited unknown corrupt Congolese government officials, In December, the International Monetary Fund (IMF) stopped a $240 million loan to Congo for failing to publish mining contracts to a company reported to be linked to Gertler.

Net worth: $5.8 billion

Beny Steinmetz is an Israeli-born tycoon, who inherited the Geneva based Steinmetz Diamond Group from his father.

The diamond jeweler's logo is "creators of the world's finest diamonds" and has been in business for about 70 years. Steinmetz is also the founder of the Beny Steinmetz Resource Group (BSR Group), which owns the Octea Diamond Group that has mined 10 million carats of diamonds from the Koidu mine in Sierra Leone, according to the company's website.

Some of the famous diamonds crafted by the Steinmetz Diamond Group include the 203.04 carat pear shaped De Beers Millennium Star, which took three years to cut. Another is the Steinmetz Pink - a 59.6 carat pink diamond (pictured), which was reported to be worth up to $100 million in 2003.

Net worth: $19.6 billion

Cheng Yu-tung, honorary chairman of the world's biggest jewelry retailer by market value Chow Tai Fook Jewellery Group, has wealth estimated at $19.6 billion, more than triple that of his closest competitor Beny Steinmetz in the world's richest diamond owners list.

Cheng is also the oldest person in the top 10 at 87 and the only Asian diamond owner to make the list. Hong Kong-based Chow Tai Fook Jewellery has grown from the opening of its first store in Macau in 1938 to now including an extensive network of over 1,800 jewelry and watch stores across Greater China. The jewelry business is one part of the tycoon's vast wealth, with business interests in real estate, infrastructure, retail and hotels.

Cheng made headlines in 2010, when he paid $35.3 million for the 507-carat Cullinan Heritage diamond, making a world record for the highest price paid for a rough diamond. Market watchers had expected the diamond, one of the biggest high-quality rough diamonds ever found, to sell for $25 million.