Is this river sand or sea sand? I see small shells in it. thank you

According to the information you provided, it is difficult to determine whether it is river sand or sea sand, because both river sand and sea sand may contain small shells. But generally speaking, sea sand is more likely to contain the remains of marine life such as shells, while river sand may contain more minerals and soil components.

If you can provide more details, such as the source and appearance characteristics of this sand, I may be able to provide a more accurate answer. For example, if sand is extracted from rivers or lakes, it is probably river sand. If sand is extracted from the ocean or the beach, it is probably sea sand. In addition, the characteristics of sand, such as color, particle size and moisture degree, can also provide more clues.

In a word, whether it is river sand or sea sand, it should be clean, free from impurities, odor, pests and diseases, and meet the requirements of health and safety. If you are in doubt about the quality of this sand, it is recommended to consult relevant professionals or local government departments.