Thin strip crystals are grown by pulling the growing crystal from the melt, through a thin slit, the walls of which are not wetted by the melt. The stability of growth at the edges of the strip is achieved by maintaining the pressure of the melt adjacent the interface between crystal and melt above a critical level which is such as to cause the meniscus of the melt to be convex on all sides of the growing crystal. The critical pressure is defined as2S/b+.sqroot.2SzgwhereS is the surface tension of the crystallizable materialb is the thickness of the slitz is the density of the meltg is the acceleration due to gravity;and the depth of the slit is at least (2S/zg).sup.1/2, preferably (32S/zg).sup.1/2 to ensure that a pressure exceeding the critical pressure can be developed and maintained without the liquid spilling out of the slit. The walls of the slit can be parallel or divergent in the direction in which the crystal is pulled, this divergence being necessary with certain materials. An arrangement is disclosed containing a head of the melt for creating the required pressure. An alternative arrangement is disclosed in which actuating devices, such as hydraulic piston and cylinder arrangements, create the pressure.