nostr:npub1fgml4kcpwj2wfnyxx5zss95up9adrkjsgtrx27e50mhwh8d45n4s3f8m7d vermiculite has a fair amount of air vs sand? you may need to do it in a more controlled ramp with a furnace  

i was able to temper A2 to a blue color and it worked when i was making a tool. can't recall exactly what the project was off hand