Ann: ADD Replicates Maiden Massive Nickel Sulphide Intersection, page-26

On sulphide melts in magmatic style nickel deposits:

The formation of nickel sulfide deposits begins with the emplacement of a magma chamber in the Earth's crust. The magma is typically rich in sulfur and other elements, including nickel. As the magma cools and crystallizes, it undergoes a process called fractional crystallization. During this process, minerals with different compositions and densities start to crystallize and settle at different levels within the magma chamber.

Nickel-rich sulfide minerals, such as pentlandite (Fe,Ni)9S8 and pyrrhotite Fe(1-x)S, have a higher density compared to the surrounding silicate minerals. As a result, they have a tendency to concentrate in the lower parts of the magma chamber. As the magma continues to cool and crystallize, the concentration of nickel sulfide minerals increases, and they may accumulate in significant quantities.