Abstract: Apparatus and method for controlled growth of large single crystals in plate/slab form from a melt, characterized by a crucible having a narrow thickness dimension that is small enough to permit adequate control over the growth interface across the full width of the crucible and a scalable larger width dimension permitting the growth of crystals having a width many times the thickness of the grown crystal. The apparatus and method are further characterized by side heating members located in close proximity to the wider side walls and the hence the melt across the width of the crucible for obtaining and maintaining control over the growth interface. The apparatus and method are scalable for the growth of large single crystals such as 1 meter by 1 meter square crystals which heretofore were not obtainable by known apparatus and melt growth methods at least in the case of single crystals such as calcium fluoride.