A semi-liquid metal processing and sensing device comprising a crucible that is at least partially encircled by at least one induction coil. The one or more induction coils can be water cooled. The one or more induction coils can be designed to generate a variable power and/or variable frequency magnetic field which can be modulated to control the cooling of a molten metal charge in the crucible from the liquidus temperature to a selected heat content, resistivity and/or viscosity. The magnetic field can be designed to induce toroidal agitation of the metal charge in the crucible. The semi-liquid condition is sensed and can be actively controlled by the induction power supply via real time or non-real time analysis of electrical feedback signals that are obtained from the induction coil.