It appears to be a stone Agate marble. If you put a light on it and move the marble around in your fingers the light reflection on the surface should jump around if it is hand faceted. If you have a hard time seeing it, do the same with a glass marble for comparison.
Be sure the photos you upload show the marble as it looks in your hand. It really makes it difficult when you show the same marble as different colors in different pics - it makes me think that none of them are showing the correct color. Size can also be important for ID.
Having said that, I don't think this is a CAC.