>>11879098It's a bismuth crystal. You can get them off Aliexpress for like 10 bucks.
Fun fact:
>Bismuth was long considered the element with the highest atomic mass that is stable, but in 2003 it was discovered to be extremely weakly radioactive: its only primordial isotope, bismuth-209, decays via alpha decay with a half-life more than a billion times the estimated age of the universe.[4][5] Because of its tremendously long half-life, bismuth may still be considered stable for almost all purposes.[5] 
