These were all made by an architect, using rubber bands.
A part of the Milev Architects's Recycling of the Architectural Office collection, the M2 line is made from office stationary, which the designers think will become redundant due to the use of computers.
The architect behind this project, Margarita Mileva says:
The ever-changing character of the contemporary architectural office, where standard tools become obsolete, in lieu of digital technology, inspires this particular collection of necklaces. For the collection Recycling of the Architectural Office I am reusing paperclips, punched business cards, eyelids, rubber bands, mosaic stones, presentation wire binding elements, ribbons, etc.See and read more about the project over at Dezeen