Jourdan Dunn is a catwalk star – can she become a cover star too?

A black single mother from Greenford, west London, reaching a Forbes rich list is not an everyday occurrence. But that 24-year-old model Jourdan Dunn has managed to scale those well-paid heights in an industry renowned for its slow progress on diversity is another reason to celebrate her ascendancy.

She is the first British black woman to feature on the business magazine's list of the highest-earning models, having raked in £2.4m in the year from June 2013 to date. That sum is in part thanks to lucrative cosmetics deals with Maybelline and Burberry, but in no small way related to her bankability as a personality.

Dunn was one of the troupe of supermodels to star in the Olympics closing ceremony in 2012, she hosts her own online cookery channel, and she starred in the music video to Beyoncé's XO last year. A 30-second clip of her doing the Harlem Shake dance craze has notched up more than 1.6m views on YouTube and, until the World Cup, she was dating footballer Daniel Sturridge.

It is the holy grail of modelling to become more name than face, and Jourdan Dunn is a commercial force to be reckoned with – one that is not afraid to question racial standards and magazine mores, and one that chimes perfectly with a social media-savvy – and shop-savvy – demographic of young women for whom race does not seem to be the same issue it was for previous generations.

She speaks with some frequency of (the lack of) diversity in the fashion industry. An oft cited fact is that, since 2002, Vogue has had no black model featured as its cover star (very infrequently a black model will appear as part of a group shot on the cover). In continuing to voice her views, Dunn has an impact beyond the catwalk and is helping to raise the debate in the UK and US.

Dunn's catwalk career has made an impact from the very outset – starting in autumn 2007, she was cast for Marc Jacobs and Ralph Lauren in New York. A year later she was the first black model to walk in a Prada show for a decade. That season, she took 75 shows in her stride across all four fashion capitals.

Dunn is not the only black model to have made waves in the industry. Naomi Campbell was the first to feature on the cover of French Vogue in 1988 and the second to make the front of British Vogue in 1987 (after Donyale Luna in the 70s). In fact, Campbell's earnings at their peak far exceeded Dunn's, but Forbes had not realised the twin pleasures of looking at beautiful women and how much money they make during her career heyday. They introduced their models rich list in 2006.

The likes of Iman, too, a Somali refugee spotted on the streets of Nairobi, and Alek Wek, a Dinka immigrant to the UK during the Sudanese civil war in the 90s, have had a hand in changing perceptions of beauty across the fashion industry. But successful black models remain few. The exposure their careers are given is far beneath what white counterparts can expect. That is why Dunn is to be celebrated for bucking the trends in an industry known for following them slavishly.

Her popular touch has a lot to do with it. Around 182,000 Twitter followers and 742,000 on Instagram give her quite the corporate clout; this is a reach that brands are only too happy to buy into. It is real-time proof that in certain quarters (notably, the audience that brands are now looking to groom) race does not come into the equation.

"Some clients book models based on their follower numbers now," says Megan McCluskie, a casting director at a glossy magazine. "And models like Jourdan are experts in getting a brand's message out to a young audience in a more natural and organic way. Jourdan feels more relatable and accessible – she wants to be listened to."

It is of no small relevance that fashion labels working with Dunn are piggybacking on the social media reputation she has built for herself – this is also the outlet for her opinions, some of which are righteously forceful on the subject of race in fashion.

As an example, Dunn has a sideline in publicly calling out those followers who confuse her with a fellow woman of colour, the Puerto Rican model Joan Smalls (also on the Forbes list). This is at once amusing and hideously awkward, but also genuinely progressive in vocalising the problems with the visibility of black models.

It is also reflected in the work that Dunn chooses, too – this season's Balmain campaign features Dunn and five other ethnically diverse women, a grouping meant to mirror the label's creative director Olivier Rousteing being "a black boy in a really important French house", as he told Womenswear Daily recently. Other publicity for the label features Rihanna, Naomi and Iman, too.

While progress has been undeniably slow as the industry gauges what impact all this has on sales, it is part of a certain motion towards greater inclusivity – at Givenchy, Riccardo Tisci has cast singer Erykah Badu in campaigns; for Miu Miu, 12 Years a Slave actress Lupita Nyong'o posed as spring 2014's muse.

Nyong'o has also been a celebrated presence at award ceremonies and on front rows throughout the year; brands have rushed to dress and associate with her. It might not sound much, but this is the sort of champion black women need to make in order for their voices to be heard in the fashion industry. In February, Nyong'o starred on the cover of Dazed & Confused.

"We're an independent publisher, so as a team we decide who we want to support," says Isabella Burley, the magazine's editor. "This is always solely down to talent – race doesn't come into play. I'm sure it's a very different story at other publications."

Indeed, there seems to be more flexing of the diversity muscle in the commercial market right now than in the editorial one – perhaps for the fact that clothing brands are feeling more resilient than magazines, battening down their hatches as readership falls. Or perhaps it is a question of demographic: if, as the numbers still suggest, black models sell fewer copies, can profit-minded publishers be found at fault, or is it their readers who dictate the pace of change?

"I think catwalk shows are where we need to see more diversity," says McCluskie, "as that's where models start out and that's their chance to be seen.

"Designers tend to take the blame, but it follows the money – Asian models have become more prominent with the rise of the Asian market. Russian models, too. The idea that the fashion industry just doesn't envisage its goods being bought by black customers seems ridiculous."

Still, if progress is tied to economics and if this is why the high-end remains – statistically, at least – so cautious about using black models, then Dunn is proof of incipient success at least, of a more accepting youth culture mindset that will mature as her followers do to bring about greater parity of skin colours on show everywhere else.

"Jourdan is one of those girls that just has it," says Topshop's creative director, Kate Phelan, who first styled Dunn for the brand's campaign in 2008 and in whose shows she is a catwalk regular. "She's a superstar, a high/low girl – whether at Nando's or the Met Ball, she has this real sense of fun.

"She's a perfect blend of cool London with beauty and a sense of humour. This is what makes her a Topshop girl, and this is why she has featured in so many of our shows and campaigns."

Given that endorsement, plus the backing of one of the market's strongest forces – the teenage girl – Dunn seems destined to climb further up the Forbes list with every passing year. Not only that, it will be exciting to see who she brings with her as well.