2515 - Marble, travertine and other calcareous monumental or building stone of an apparent specific gravity of 2.5 or more, and alabaster, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape:

This HTS category, 2515, encompasses marble, travertine, and other calcareous monumental or building stones. To qualify for this classification, these stones must possess an apparent specific gravity of 2.5 or greater. Alabaster, regardless of its processing state, also falls under this heading, provided it has been roughly trimmed or simply cut into blocks or slabs of a rectangular shape. This section is concerned with naturally occurring stone materials primarily intended for use in construction or as decorative elements.

Distinguishing HTS 2515 from its sibling categories within Chapter 25 is crucial. Unlike inorganic materials such as salt (Chapter 2501) or sulfur (Chapter 2503), or even earths and stone not specifically defined as monumental or building stone, HTS 2515 focuses on a select group of calciferous rocks and alabaster. These materials are characterized by their suitability for quarrying and shaping for architectural, sculptural, or decorative purposes, often due to their aesthetic qualities and durability.

Within HTS 2515, further subdivisions clarify the specific types of stone. The subcategory for "Marble and travertine" isolates these two widely recognized and valuable calcareous stones, known for their distinctive veining and polishing capabilities. The remaining subcategory, "Other calcareous monumental or building stone; alabaster," consolidates other suitable stones that meet the specific gravity and application criteria, along with alabaster, which, while chemically different, is grouped here due to its common use in monumental and decorative applications alongside calcareous stones.