The telephone-installation is a memorial to the more than 3 million people who have perished in the complex wars that have gone on in the Congo since 1998, often referred to as the “Coltan Wars”. The ore coltan is used as the raw material for the metal tantalum, which is an essential component of mobile phones and computers. Therefore tantalum is coveted by dozens of international mining industries and local warring groups, and is nowadays more valuable than gold. Built of electromagnetic “Strowger” telephone switches, invented in 1938, and connected to a computer, the installation serves not only as a memorial, but functions also as a center of a social telephone network that is used by Congolese immigrants living in the UK. The network Telephone Trottoire builds on the traditional Congolese communication practice of passing around news and gossip from pedestrian to pedestrian on the street to avoid state censorship. In cooperation with a London based radio program it calls Congolese listeners and plays messages, which can be commented and forwarded. The project, which classifies as a mean of communication between tradition and modernity, can note so far about 1.800 users. In 2009 Tantalum Memorial won the transmediale.09 award in Berlin.