is plotted as a function of distance between the top of the silicon melt and a fixed reference point within the hot zone as the mass of silicon in the crucible increases the distance between the top of the melt and the fixed reference point decreases this data was collected prior to introducing a silicon seed crystal therefore the height measurement was not obstructed by the growing ingot thus allowing a direct correlation between melt height and crucible weight the data points in fig4 illustrate the ability to measure weight and thereby control the mass of silicon melt in the growing environment allowing precise control of the volume mass of initial silicon melt at the beginning of the process and or the volume mass while adding feedstock during growth using weight to determine the mass of silicon melt in the crucible eliminates the need for a visual reference and the need for a reflective melt surface fig5 is a data plot showing the weight of a silicon melt decreasing and the weight of an ingot increasing as a function of time as silicon is consumed from the melt by a growing ingot notice that the crucible weight decreases as the ingot weight increases which is indicative of growing a crystal when an ingot is growing the visual reference for melt height is obstructed and it is difficult to determine the mass of silicon in the melt according to an aspect of the invention this plot demonstrates.