"My parents came to Hong Kong from India when they were young. My grandfather passed away so my father got a job selling coloured stones before branching into diamonds and manufacturing jewellery. By the late '70s he had set up his own company, so my brother and I grew up in the business," explains Manoj, who studied at business school in New York with his brother.

By the late '90s the brothers were enjoying high-profile jobs in banking when their father approached them to join the family business. Intrigued by the proposition they moved to Hong Kong and started from scratch. Over the next decade they implemented a few changes, including the addition of stock, while expanding the private client and wholesale business by attending trade shows such as Baselworld.

"Dad gave us good advice - he said don't flex your muscles, absorb what you can, understand everyone's role. After a certain time, we realised the true value in what we are doing is to create a legacy - not for ourselves but also for our children.

"Now is the time to build a brand - we have a good name within the trade but no one knows us from the street level. We manufacture jewellery for a lot of major brands around the world, so there's no reason why we can't stand on our own," says Manoj.

The first step came in 2007 when Butani was offered a space at the soon-to-be-opened Venetian shopping mall in Macau. It wasn't long before others followed, including the Grand Hyatt in the City of Dreams, the Sheraton in Cotai Central and the flagship at The Peninsula earlier this year. The jump from wholesale to retail brought new challenges, including managing staff to creating interiors for the new boutiques.

The biggest change can be seen in the product itself. Although a large portion of Butani's business still comes from bespoke orders, the brothers recognised the need to develop a brand identity and offer jewellery that would appeal to a wider audience. So they established a team of six designers based in Hong Kong and Italy to create collections for the stores.

"Now we have four stores, we are starting to build our own collections that people can recognise. We are no longer a private label, but a brand," says Manoj who oversees the creative side while Mukesh handles management and business development.

The fruits of their labour can be seen in new collections such as the Bloom, a classic and timeless line based around various floral motifs and the Metropolitan, a modern collection of bangles and pendants based around different diamond shapes. More styles will follow as the boys continue on their quest to build an international jewellery brand.

"The barrier of entry into the luxury world is very hard - it costs a lot of money to build a brand. I am more keen to invest in a big piece of jewellery than to advertise but if that's what it takes we will try our hardest," says Manoj.

Like the Butani brothers, sisters Sheryl Buxani Wadhwani and Michelle Buxani Panjwani also grew up surrounded by diamonds. Their mother and aunt started the business more than 25 years ago from their dining table, offering advice to friends who wanted to invest in jewellery. Soon they were selling loose diamonds and designing their own creations.

Today the company, Temptations, has a 15,000 sq ft showroom in Tsim Sha Tsui showcasing a multitude of styles, ranging from classic to traditional Indian.

Wadhwani joined the company at the age of 22. "Both Michelle and I graduated in law then went into finance. I didn't love the hours so mum suggested I join her. While I studied gemology I also spent as much time as I could learning the business. Michelle joined me a year later," she says.

Although many of their friends expected the sisters to design their own line, they focused on developing the business and building a clientele beyond the Indian community. Soon Temptations was advertising in glossy magazines and launching social media accounts on Facebook and other platforms. By 2011 they had moved to the new showroom which offered opulent salons for private consultations.

Last year they sponsored a high-profile charity event, hosting a catwalk show featuring a new collection of custom jewels. Today they take part in a number of trade shows from Hong Kong to Dubai.

"Our Middle East business is entirely new. Initially, the majority of our clientele was Indian but now 60 to 70 per cent are international and live outside Hong Kong. Because of this our design has evolved, too - we do classical pieces as well as modern. Versatility is important so we are trying to implement this," says Wadhwani, who has started adding more ready-to-wear pieces for the collections.

Last year the company opened its first showroom outside Hong Kong in Singapore.

"The beauty of having a big family means we don't all need to be in Hong Kong. Singapore seemed a good hub for Malaysia and Indonesia. We are looking to open more in future, maybe in the Middle East and Dubai. The goal is to open to three to four different showrooms in major cities," says Wadhwani.

Although Payal Shah of L'Dezen Jewellery also hails from a family of diamond dealers, her business is a one-woman show.

"My parents were never in the jewellery business - they were diamond traders. A lot of their clients are jewellers so that was my connection to the industry," she says.

Shah studied architecture at university in London, but would often help her father sorting diamonds. It was then that she discovered sliced diamonds, which were just starting to gain popularity. She tried her hand at a few designs, enlisted a factory to produce them and took them to a show in Las Vegas in 2011. L'Dezen was officially born.

"The overwhelming response and success is what made me leave my job at the design firm. One thing I did know was if I entered the jewellery industry I was going to make a lot of contacts in the industry easily as I had been around it. I am my father's client so it works out well for him too. I wouldn't entirely call it a family business, but more of an extension," says Shah who operates as the company's chief executive and art director.

L'Dezen Jewellery consists of a wholesale section and a retail line that is sold in high profile boutiques worldwide. The ready-to-wear line treads the boundary between sophisticated and funky with modern designs that reference classics.

In four years it has amassed a strong celebrity following, including singers Lady Gaga and Taylor Swift and actress Sofia Vergara. Shah has also won a slew of awards, most notably Jewellery Net Asia's Young Entrepreneur of the Year.

She is working on an app for the jewellery industry called Insta Jewel, as well as working on designing and building a brand.

"The jewellery business is becoming saturated, so it's important to stay hot. I create one-of-a-kind items and change styles according to the seasons. I'm hoping to start a legacy of my own," she says.