In New Zealand, on Koekohe Beach there are hundreds of huge stone balls. Some spherical and smooth, some compressed and cracked. Nearby is the village of Moeraki, so they are called "Moeraki Boulders". In science such things are called "concretion and septarium", and they consist of clay and mud. But I know that it's really dragon eggs!
A photo of a large resolution is 2500х1563 px. It is better to look at it that way.
Camera: OLYMPUS E-M1MarkII
Exposure time: 13 sec
Diaphragm: F 8
Sensitivity: ISO 64
Focal length: 18 mm
35 mm equivalent: 36 mm