cylindrycal object

cylindrycal object

Observation - cylindrycal object - UK and Ireland. Description: I found this on the beach. It is a very hard glass-like when tapped on tooth. It is not obviously man-made and appears to be segmented. Any ideas

I found this on the beach. It is a very hard glass-like when tapped on tooth. It is not obviously man-made and appears to be segmented.
Any ideas