What kind of surface is a pebble tec pool?

[Karkas]

Just downloaded the app. My pool is pebble tec. Is that considered Vinyl, plaster or fiberglass?

I'm including a photo if that helps.

Thanks in advance

 

[ajw22]

PEBBLETEC is plaster with stones in it.

 

[Karkas]

PEBBLETEC is plaster with stones in it.

Thank you!! Sorry if it was a redundant question, but I did search several times only to get a lot of non-relevant answers.