Two composites based on Na silicate and Al(2)O(3) matrix and reinforced with swollen vermiculite were prepd. by cold press moulding (samples 10x10x200 mm) and studied for thermal degradn. at 200-1075 degrees C and fire barrier properties at 1049 degrees C. The addn. of the swollen vermiculite resulted In Improving of the thermal Insulating properties of the samples. The temp. on the non-heated sample surface was 128 degrees C or 127 degrees C (compared with 184 degrees C and 194 degrees C, resp., on the samples without vermiculite) after 120 h long heating at 1049 degrees C. The av. temp. Increase on the non-heated sample surface after 80 min long heating was below 100 degrees C.