N2 adsorption isotherm data of clay briquettes made from red and white clay with sand and chalk tempers fired at 600 and 800 °C. N2 adsorption isotherms of bulk sand and briquettes made from bulk white and red clay fired at 600 °C. N2 adsorption isotherms of 3 equivalent composition red clay briquettes with 50% sand temper and each measured 2 times for statistical analysis. All data files include pore size distributions obtained by fitting to the NLDFT model for pillared clays.