To prove that germs aren’t all bad, Paris-based studio Bold-design came up with an activity kit that uses bacteria to turn sand from the beach into stone souvenirs. Designers William Boujon and Julien Benayoun of Bold-design created Memorabilia Factory for the Design Exquis project that invites four designers to respond to each other’s objects in turn, like the parlour game where one player draws part of a character then folds the paper over and passes it along for the next player to make his contribution.

Bold-design was asked to respond to a portable machine designed by Mikael Metthey and Milan Metthey, which lets parents test sandy beaches for harmful bacteria to find the safest place for their children to play.

The designers came up with Memorabilia Factory, a family activity kit that uses a harmless bacterium to turn sand from the beach into solid stones in the shape of local rock formations. The kit includes a bacteria solution, a fixing agent, a tool to fix and shape the sand and three moulds, which represent Durdle Door in the UK, the dune of Pilat in France and the Kon Phi Phi islands in Thailand.