6907.23.10.51 - Other

This HTS category, 6907.23.10.51, encompasses "Other" unglazed ceramic flags, paving, hearth, or wall tiles that have a water absorption coefficient by weight exceeding 10 percent. This specific subheading applies to such tiles which are not otherwise classified within the preceding subheadings. The defining characteristic is their unglazed nature and high porosity, indicating they are not intended for applications requiring significant impermeability or a smooth, finished surface from the outset.

It is crucial to distinguish this category from its sibling, 6907.23.10.11. While both fall under unglazed tiles with a water absorption exceeding 10 percent, the sibling category specifically addresses tiles where the largest surface area can be contained within a square with sides of 30 cm or less. Therefore, 6907.23.10.51 covers all other unglazed ceramic tiles meeting the porosity requirement that *exceed* this size limitation, or are otherwise not defined by the dimensional criteria of the sibling.

As this classification represents a leaf node, there are no further subcategories. Classification into 6907.23.10.51 is determined by a process of elimination: if a ceramic tile is unglazed, has a water absorption coefficient by weight exceeding 10 percent, and does not fit the specific dimensional criteria of 6907.23.10.11, it will fall into this "Other" category. Practical classification will rely on verified water absorption test results and the physical dimensions of the tiles in question.