A:Answer Hello Annie. This is RICHARDatGEA. Cast Iron cookware is not recommended with theJS750SFSS. If the cookware has a burr or rough spot, it will scratch the glass surface. Additionally, it is slow to absorb heat. Once this type of cookware heats up, especially on high heat, it holds an intense amount of heat which is transferred to the cooktop. This can cause the element to shut down as a response to the temperature limiters which indicate surface temperature is too high for cooktop components to handle. Thanks for the question.