LEGO wants to make everything awesome for the planet. In 2015, the Danish toy-maker pledged to spend $150 million and hire more than than 100 extra staffers to research and develop sustainable alternatives to the petrochemical-based plastics it uses to make its signature building blocks. The goal, the company said then, was to transition to either a bio-based version of acrylonitrile-butadiene-styrene, its current primary raw material, or a polymer with a lower environmental footprint by 2030.

LEGO, eco-friendly toys, wind power, Tim Brooks

Finding a suitable replacement, however, has proven thornier than anticipated. “We want any bio-based material to be capable of being precisely molded, or to mold to just a few microns,” Tim Brooks, vice president of environmental responsibility for the LEGO Group, told Quartz. “And we want it to be shiny.”

Manifesting that gleam has proven to be a stumbling, well, block. Next to a traditional plastic brick, a prototype brick made from wheat sugar appears dull and matte.

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LEGO, eco-friendly toys, wind power, Tim Brooks

Not that LEGO is going to give up, of course. Climate change is real, and the world’s leading companies will have to rein in their fossil-fuel use if the human race wants a fighting chance at survival.

“We know that making bricks has an impact on the planet, and we want it to be a positive one,” Brooks said.

+ LEGO

Via Quartz