Natural kaoline was intercalated with NH2NH2, HCONH2, Me2SO, K and Me acetates, HCONHMe, imidazole and urea and then heated in microwave field (2.45 GHz, 100-800 W) to develop the sp. surface of the original kaoline (19.0 m(2)/g) by thermal decompn. of the intercalating mols. The increase in the sample temp. during the microwave heating up to above 450 degrees C was obsd. The intercalation with NH4, and K acetates resulted in the highest increase in the sp. surface to 49.4 m(2)/g and 40.6 m(2)/g, resp. The dry pressing of the samples contributed to an increase in their sp. surface. The effect of sample size on the sp. surface after heating was also remarkable.