What is fire clay and where to get it in nature
All refractory are based on fire clay, what it contains, alumina and silica. In fact all high heat resistant firebricks are made of fire clay. Like heat resistant mortars, insulation, pottery, ceramics, ceramic blankets or ceramic tiles on space shuttle, origins of these start from the fire clay, its melting starts at 1600 Celsius °C or 2912 Fahrenheit °F point.