Neclumi is a necklace that you can’t touch, or buy, or get insured. Rather, it's a pattern of tiny light projections that beam onto the wearer’s neck, and according to Neclumi’s inventor, its presence on a jewelry blog sparked some backlash. It’s not silver or gold, reasoned the commenters, so it’s not jewelry.

“We have less and less of our own things,” says Jakub Kozniewski, one of four artists that make up panGenerator. “We don’t have books, we have data that lives in the cloud. We don’t have CD cases for music, it’s all streamed through Spotify. With the same logic you could stream jewelry, or treat it like software.”

Kozniewski and his collaborators at the Warsaw-based art collective created Neclumi while experimenting with projection mapping and with wearable devices. They’re often tinkering with technology (last year panGenerator created another conceptual wearable, called Tactilo, that lets two wearers send each other haptic signals over Bluetooth signals) and decided to see what would happen if they fused projection mapping with wearables to create wearable projections. The result is Neclumi, an app that pairs with a picoprojector, attached to a shirt collar, to shine little light tattoos on the wearer’s neck, like a glow-in-the-dark choker necklace.

Right now Neclumi (which is still very much a prototype) has four ‘styles’: Airo, Movi, Roto, and Sono. Each one responds to different sensors to flicker and flutter and expand in size on the wearer’s skin. Movi, for instance, reacts the phone’s accelerometer and changes its pattern according to the wearer’s body movement. Roto, on the other hand, contracts in tandem with the phone’s compass.

Neclumi has a ways to go before it’s market ready. Right now the picoprojector connects to the smartphone via an HDMI cable, so Kozniewski says they would need smaller batteries and chips to make it a standalone necklace. Still, it’s easy enough to imagine Neclumi showing up as a future app available in wearable bracelets once projectors become small enough to neatly snuggle into devices. Light projected jewelry could even be a clever antidote to the problem faced by wearable-makers who want to make their wares more customizable but don’t know how. Kozniewski even imagines that the projections could help people–perhaps with hearing disabilities—tap into new ways to communicate. “How could you use the sensors to creatively express the user visually?” he asks. “I think the necklace is poetic, there’s something romantic there—a bigger trend apart from the jewelry.”