Asian designers, including (from left to right) Aya Kamimura, Huang Chaoyan, Liu Fei, Tong Wenwei and Zhong Hua are invited to collaborate on Rio Tinto's Diamond Fashion Jewely collection.

"It's known to all that the Chinese market is growing rapidly," Lieberherr says. "There are tens of millions of new households expanding the middle-class segment. They aspire to diamonds, fashion and jewelry, but the supply remains rather stable, mainly for the bridal market."

Liu, the designer, called the mainstream Chinese diamond market a "conservative one", which is rather "dull" for a designer, while small diamonds allow more room to unleash the creative power of designers.

The latest figures from the Hong Kong Trade Development Council show that more than half of the jewelry purchases on the Chinese mainland resulted from weddings. In 2012, the annual sales of China's gold jewelry hit 400 billion yuan ($65.6 billion).

Rio Tinto's Diamond Fashion Jewelry series

Yet, it is believed that an equally large, if not larger, market for the independent, sophisticated and usually single urban woman remains untapped. The company estimates that by 2020 the market for diamond fashion jewelry will reach 36 billion yuan.

"Affordable and fashion-driven diamond jewelry is already a popular trend, but the number of products available on the market remains limited," says Jing Jing, executive publisher and editor-in-chief of Harper's Bazaar Jewelry.

"Chinese women are very quick and talented in embracing new trends. A decade ago, the market consisted mostly of 24k yellow gold, while today 18k and white and rose gold are everywhere. The trend of diamond fashion jewelry is set to develop in the same way," she says.

The idea of fashion jewelry, or say, "affordable luxury jewelry", as it is generally marketed, is nothing new in China.

The Austrian precision-cut crystal producer Swarovski has won the hearts and purses of millions of Chinese women with its motto "a diamond for everyone", since it came to the country two decades ago.

Early in November, the company brought its Runway Rocks collection to Shanghai for the first time, by collaborating with the newly opened Lane Crawford department store.

A trailblazing collection of the brand, it gathers works from the world's top designers to push the boundaries of fashion jewelry design. In Shanghai this year, a total of nine Asian designers, including Guo Pei, Zhang Huishan and Masha Ma, were invited for the project.

But the advantage of diamonds against the lower-priced yet similarly sparkling crystals, as Lieberherr believes, is "diamonds (are more valuable)".

"The diamond is the thing. It's unique. It shines like nothing else, with a very special luster that is unbeatable," as he puts it. Or as Marilyn Monroe sang: "men grow cold as girls grow old ... diamonds are a girl's best friend".