... harmlessness, used for fireplace, stoves, wall, firedoor core, pipe protection... It is made of expanded vermiculite board. The ... Expanded vermiculite2 Working temp:1100degrees3 Advantage: Natural, environmental-protection orientated, no poison and no radioactivity Fireproof, damp- ... thermal shock,flame and airflow attack Resistance to corrosion,high compressive strength. High toughness,easy to cut ...