Does any one have, or has anyone used vitrified clay pipe as a riser? It would be insulated with rock wool. The pipe is supposed to be able to take over 2300 degrees f.
Clay tile/pipe can stand high temperatures, but it cannot handle fast temperature changes like you get in a RMH core. People who have tried it have found that the tile cracks, sometimes badly.
My sister got engaged to a hamster. This tiny ad is being too helpful:
