Color/Yellow

Yellow pyramids were released in 1999, one of the first colors of die-injected plastic pyramids ever to be produced. They were first sold in a clear acrylic box of the game Icehouse: the Martian Chess Set, which contained 15 yellow pyramids along with equal amounts of red, green, and blue. Yellow pyramids are a transparent, and are given the designation "Rainbow" in the Rainbow vs. Xeno classification system.

Trivia

The color "Electric Yellow" is called yellow, but looks very different from the standard yellow pieces. Electric Yellow was produced in such low quantities that there is likely to be little confusion between the it and the standard yellow pyramids when reading game instruction manuals.