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BARCELONA, Spain--Part of what makes Nokia phones like the Lumia 920, and the new Lumia 720 and Lumia 520, so distinctive are their bright color options. And part of what makes those shades pop is the use of polycarbonate, a type of plastic, as the body material.

Although Nokia hasn't ruled out an all-metal body, speaking at Mobile World Congress with Hans Henrik Lund, Nokia's vice president of product marketing for smart devices, makes me think that we won't be seeing metal Lumias anytime soon.

"The important part for us is that we're obsessed with differentiation," Lund said. He goes on to tell how a 9-year-old boy shouted the name "Lumia" and pointed when Lund snapped a photo of Istanbul's Blue Mosque with his yellow Lumia 920 smartphone.

That kind of brand recognition is certainly achievable with colored metal, but Lund's point is that creating a recognizable product that stands out from the crowd is a central Nokia goal. In other words, expect a phalanx of polycarbonate Lumias to march down the pipeline in the coming months.

I also suspect that cost considerations have a lot to do with the polycarbonate choice. Nokia is focused on offering like-looking Lumias that span the price point from low to high, a plan that metal might muddle.

In addition, many Lumia phones are already weighty enough on their own without adding a potentially heavier material to the often-larger frame and components.

For all we know, metal elements could be in the works for high-end Lumias further out on the road map, but in the meantime, Nokia lovers would be better off embracing the Lumia line's youthful design.

Read even more smartphone news from Mobile World Congress.