This is a hollow tube implosion marble that measures 1.64 inches in diameter. This has a Star cluster milli I made in the center of the marble and blue spruce, forest green, Roswell green and green slime litticino aka my colorful worms. Black galaxy sparkle on the back of marble and it reacts in UV light a bit. Full disclose a small air trap of some sort flits above tge design so I am asking less for this one than I normally would but just because I notice it doesn’t mean it bothers someone else 😂. Free 3D printed marble stand included as well as free shipping through my web site right now.