Just FYI this is illegal in many areas.
As such, it's completely normal that you can't just take sand or stones from many beaches. The very famous Étretat town in France with its accompanying beach and rocks, have a very strict "don't take souvenirs from the beach because you'd be actively destroying it" policy.
Canadian National Parks[2] and most Provincial/Territorial Parks.
[0]: https://www.nps.gov/articles/recreational-collection-of-rock...
[1]: https://www.ecfr.gov/current/title-50/chapter-I/subchapter-C...
[2]: https://parks.canada.ca/voyage-travel/regles-rules#objects