Outside the bounds of mega-mainstream pop celebrities - the likes of Madonna, Kylie Minogue, J. Lo, Beyonce, Rihanna and Katy Perry - who are so famous they get chased for product placement and ad campaigns regardless of what vibe the divas are projecting at any given time, the kind of musicians who wind up in the fashion fold is very particular.

To be a musician favoured by fashion requires a peculiar blend of attributes that often have little to do with actual ability in one's initial field of fame.

The Kills, for example, have had lukewarm critical reception in musical circles, but they are worshipped by the fashion set. Thanks to a combination of frontwoman Mosshart's good looks and penchant for publicly discussing her fondness of Slimmane-era Dior Homme, Hince's relationship with Kate Moss and an immaculately maintained aura of disaffected cool that holds enormous appeal for the aspirational/inaccessible quadrant of the fashion industry, the band are more likely to be found on the style than sound pages.

Florence Welch's distinctive ethereality has seen her flourish rapidly into a fashion muse, while Sky Ferreira has been so gravitationally drawn to front rows, magazine pages and fashion parties, you could be forgiven for forgetting she's even releasing an album.

The latest musician to pique interest in rag trade circles is Lana Del Rey, who just inked a contract with major agency Next. This puts her on the same books as the far more mainstream Jessie J, style-icon MTV host Alexa Chung and Chanel's latest bag lady Alice Dellal.

The signing follows a brief blogosphere flare-up that Del Rey had landed a Prada campaign, following the release of a doctored image of pouting Del Rey in Miuccia's signature lips print, lifted from the pages of Wonderland magazine. With her chequered background (did she grow up in a trailer? was her dad a dot-com boomer? are both true?) and soulfully sad delivery of lines like "I heard that you like the bad girls, honey" Del Rey would've made sense for Prada's fifties Americana "what men want is cars and girls" Spring/Summer 12 collection.

Undeniably gorgeous, a this-season Del Rey would feel extremely fresh for luxury consumers, most of whom probably don't follow indie blog hype storms and scraps over artificial image-making, and therefore have no idea who the doe-eyed, sad-faced songstress is.  

Del Rey's sound is also fashion-friendly; old-worldy-moody, pretty and in a lot of ways utterly unintrusive, it has already made it onto a number of catwalks.  

While looking good in clothes and crafting runway-ready tunes are two important ingredients in becoming fashion-famous, I question whether Del Rey will ever truly be embraced by either luxury brands or the high street.

This is because she lacks a third heat. Unlike Welch and Mosshart, Del Rey does not seem expensive. Her essentially A.C. sound is produced, filled-out, yet mellow enough to work in the high end, but her image (wearing denim hot-pants and kissing beautiful tattooed boys in "Born To Die", absolutely everything about "Video Games", her plastic nails and those unashamedly inflated lips, her tendency towards racing jackets) smacks of the trailer park. Her beauty has the same  kind of tragically captivating white trash aura as Anna Nicole Smith's, and it's an intentional effort, emboldened by her questionable backstory.

 While this kind of imagery would be ideal for a Guess? campaign, her musicality is too restrained, it lacks the fun, vibrant danceability of offerings by high street heroines like Jessie J and Ellie Goulding. Del Rey would perhaps have worked for Urban Outfitters, but as their revenues sink through the floor, they're a poor niche to target.

Though Del Rey is distinctive, her standout-ishness smacks more of the now - fashion is having a very retro-femme moment, as that Prada rumour will attest - than of her. Show stoppers of style like Amy Winehouse, MIA and Beth Ditto did not fit into a moment that was happening already, through forcefulness of character, they made their own.

The reason why you do not see musicians frequently fronting campaigns, luxury or otherwise is because, for reasons I suspect have to do with the deep-nicheness of musical taste, they typically do not track well. Even Lady Gaga, who some would argue is the ultimate fashion-musician, sometimes struggles to shift magazines. As far as less exposed musicians go, in order to be worth a brand's money, an act has to be either so flawlessly on-point (Welch playing at an ocean-themed Chanel show, Jessie J for House of Holland, MIA in Ashish) that even those who dislike the artist's output can see the sense in the alignment, or so shockingly incongruous it generates column inches (the Winehouse themed Chanel show, everything to do with the luxury Beth Ditto has ever done). A Prada campaign, at this early stage in her career, would have been both of those things at once for Del Rey, but whether either kind of moment will come again for the buzzed-about singer is questionable.  

Del Rey is in a position where, though she has the looks to pull off a transition into fashion, her sound and personal branding are out of alignment. It is for that exact reason that she caused such buzz in the music world, the idea of a 'gansta Nancy Sinatra' has immediate headline appeal and debates about authenticity are such enjoyable merry-go-rounds it is hard to resist hoping on. In the carefully calculated world of fashion, however, image is more about a hyper-focused push towards a unified aspiration (a 'full look' if you will), than an intriguing tangle to be combed through, so incongruities are an enormous liability.

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