Jasper!

Likely Possibilities:
* Jasper: This is a common type of chalcedony (microcrystalline quartz) that comes in a wide variety of colors and patterns, including orange and brown. The opaque nature and the somewhat mottled or brecciated appearance in the image could suggest jasper.
* Agate: Another form of chalcedony, agate is typically translucent to transparent and often exhibits banding. However, some agates can have more irregular patterns with orange and brown hues.
* Brecciated Sedimentary Rock: This type of rock is composed of angular fragments of other rocks cemented together. The different colored areas in the image could represent these various fragments.
Less Likely, but Possible:
* Some types of metamorphic rock: Certain metamorphic rocks can have complex patterns and colors, but they often exhibit more foliation or layering than what's clearly visible here.
* Weathered Igneous Rock: While less common to have these specific patterns, heavy weathering can alter the color and texture of igneous rocks.
To get a more accurate identification, it would be helpful to know:
* Where was the rock found? (Geographic location can narrow down possibilities).
* What is its hardness? (Can it scratch glass? Can it be scratched by a fingernail?).
* What is its luster? (Is it shiny, dull, glassy, etc.?).
* Does it have any visible crystal structure?
* Is it heavy or light for its size?
Without this additional information, a precise identification is not possible. However, jasper is a strong possibility based on the image provided.