Based on the appearance of the rock in the image, it looks like it could be a type of chalcedony, specifically an agate. Agates are known for their banded or layered appearance, often with translucent to semi-translucent qualities. The rock in the image shows a mix of colors and a somewhat banded structure, which is characteristic of agates. They commonly form in volcanic and sedimentary rocks and are often found in cavities or veins.