Physics of strange matter for relativistic heavy-ion collisions

Relativistic heavy-ion collisions offer the possibility to produce exotic metastable or even absolutely stable states of nuclear matter containing (roughly) equal number of strangeness compared to the baryon number: Strangelets, small pieces of strange quark matter, were proposed as a signal of quark-gluon plasma formation. As their hadronic counterpart, also small pieces of strange hadronic matter may also show up with rather similar properties. The reasoning of both their stability and existence, the possible separation of strangeness necessary for their formation, and the chances for their detection, are reviewed.