The site, which launched just 18 months ago, focusses on "smart, creative, shareable content", with articles that are either under 500 words or longer, more analytical pieces.
Speaking to Journalism.co.uk, Kevin Delaney, editor-in-chief of the site, said he believed Quartz's rapid growth was down to its strategy for being "as optimised for the free, open social web as possible."
He added that traffic to Quartz, based on Omniture figures, had increased by around one million every quarter since the site launched in September 2012.
Further, he said that advertising revenue was also tracking to be up more than 400 per cent over the first quarter last year, with Quartz adding more than 40 blue chip accounts to its client roster in the last 12 months.
Mobile is Quartz's fastest-growing audience, with 41 per cent of unique visitors viewing the site on a tablet or mobile phone in January.
I'm surprised that it was "only" 41 percent.
More than 50 per cent of the site's overall traffic also comes from social media, said Delaney. This is something he attributes to the "Quartz curve" – the belief that the most shareable content is either under 500 words or more than 800.
"Articles of between 500 and 800 words are too long to be sharable, and too short to be in-depth," he said at an event in October last year.
Why Quartz does not publish 500 to 800 word articles - "Kevin Delaney, editor-in-chief of business news site Quartz, suggests that online news publishers ditch 700-word stories"
Another way Quartz makes the most of social shareability is to exploit the visual nature of the web, with roughly half of posts including some kind of graph or chart.
"Charts are very native to a business environment," said Delaney, "and they're also a really efficient way to communicate information generally rather than forcing someone to read 900 words about a complex topic."
And data visualisation is an area Quartz will be investing in over the next 12 months, he explained.
Quartz has already open-sourced its Chartbuilder platform, a tool for newsrooms that is currently being used by outlets including The New Yorker, CNBC and NPR
The Quartz team have also developed the data mapping tool Mapbuilder, currently being refined and so only being used internally, but the plan is to make that open-source as well.
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