Chalcedony, maybe jasper...need better photo.
See if light passes through it. Backlight it with a flashlight,
From the picture it doesn't look transparent, which would indicate jasper as a most likely candidate. Also see if you can test the hardness - see if it will scratch a piece of quartz.
It is opaque.
It does not scratch quartz.
Can you test its streak? Does it have a white or a brownish streak?
Ok then its definitely not Jasper. Were you able to test hardness? Perhaps its hematite. Is it heavy? It could also be a waterworn brick or hardened sandstone.