Chalcedony glow!

This rock appears to be a type of agate, specifically a form known as Banded Agate or Fortification Agate. Here are some key characteristics that led to this identification:

Banded Structure: The rock shows clear banding, which is characteristic of agates formed in cavities where silica-rich solutions deposit in layers over time.
Translucency: Parts of the rock are translucent, which is typical for agate due to its chalcedony composition.
Color Variations: The presence of various shades like white, brown, and hints of yellow or orange indicates different mineral inclusions or variations in the silica deposition process.
Patterns: The patterns resemble a fortification or landscape, which is common in fortification agates where the bands follow the outline of the cavity in which they formed.

Agates are a variety of chalcedony, which is a cryptocrystalline form of silica, and they often contain colorful bands or layers due to changes in the composition of the depositing fluids or the presence of different minerals. This particular specimen seems to have been polished or naturally smoothed, enhancing its translucency and the visibility of its internal structures.

If you're interested in further identification or more detailed information, I could suggest searching for similar examples or consulting with a mineralogist or gemologist.