Every so often we find international crystals in car boot sales, auction houses, in charity shops, and one time we even found an amethyst bracelet in the sand. 
These three green agates have a touch of red in the centre if you hold them up to the light. Two of them have distinct darker green and lighter green bands in them. One appears to be an eye agate. 
These have been in the desk for ages, in a bag with other international tumble stones, which we have been meaning to list for years. We will likely add to these Semi-Precious Tumble Stones over time.