According to the packaging, the Magic Window “CREATES MOVING, CHANGING PICTURES! with fascinating 'VOLCANIC ACTION." It's made of "MILLIONS OF MICRODIUM CRYSTALS." You're invited to "TURN IT OVER" AND "WATCH THE MAGIC ACTION!"
This toy consisted of two plastic "windows" sandwiched together with the multi-colored "microdium" crystals inside. The different colors of crystals didn't want to mix together, so shaking or twirling the window produced swirling patterns. The toy came in two color combinations that I recall, blue and white or pink and white.
Magic Windows were licensed in 1973, but eventually discontinued. It was the perfect seventies toy...endlessly fascinating for curious kids, and undoubtedly even more psychedelically, funkadelically, radically cool for stoners. It was, like, far out, man.