These systems usually exhibit very weak magnetic properties, and they are predominantly diamagnets. Only a handful of them allow for the use of methods developed within the solid state approach to magnetometry-these that can be bound by weakly magnetic glues without any degradation effects. One of such very con-venient bonding agents is the so-called GE varnish , which dissolves very easily in ethanol and works (bonds) down to the lowest temperatures. If the investigated material does not decompose or change its properties in ethanol, the investigated substance can be stabilized in the GE varnish and be affixed firmly to common sample holders, like rectangular pieces of semiconducting compound, and then mounted into plastic straws or deposited on Si . In all other cases, different, usually custom devised approaches had to be developed . As far as the present authors can judge, none of them can be regarded as magnetically transparent or being able to provide truly quantitative results.