Like all of Mark's UV marbles, this one is made out of 100% uranium glass, and thus it lights up like a Christmas tree on fire when you put a black light on it. Seriously, it is unbelievably bright! Often when I take the black light pics, I have to set the exposure to either 2 or 4 seconds in order to get enough ultraviolet light in there to light up the UV glass for a good shot. But with Mark's marbles, even a half second is too much! Truly amazing glass!!

This marble is from Mark's geometric air trap series, and has a pair of rectangular air traps inside of it. What's amazing is that the two air traps are on different planes within the marble, two different geometric levels of existence! A true wonder in marbledom, seriously cool. Awesome collector piece here, large and in charge!! Signed 'Matthews 2001'.