Cera Perdida (Lost Wax) is an ongoing project by Barcelona-based sculptor Tanya Sierra.

Every month Tanya leaves one of her sculptures somewhere in Barcelona for a stranger to find and claim.

Each sculpture has a URL engraved where the finder can get more info about the object. The websites contains a photo-gallery of each lost sculpture as well as messages from people who actually found a sculpture.

The project has been running from January 2007 and will end this December.

• www.ceraperdida.com