6815 - Articles of stone or of other mineral substances (including carbon fibers, articles of carbon fibers and articles of peat), not elsewhere specified or included:

Heading 6815 encompasses a broad range of articles manufactured from stone or other mineral substances, which are not specifically provided for in other headings of Chapter 68. This includes items made from materials such as carbon fibers, graphite, peat, and various other mineral compounds. The key criterion for classification under 6815 is that the article's primary composition is of a mineral substance and it does not fit into more specific classifications based on material type or intended use within the HTS.

Unlike sibling categories within Section XIII, which often focus on specific materials like ceramic products (Chapter 69) or glassware (Chapter 70), Heading 6815 serves as a residual category for mineral-based articles. It is distinct from headings that cover finished goods with a predominantly singular mineral component, such as articles of cement (heading 6810) or articles of asbestos-cement (heading 6811). The articles under 6815 are characterized by their diverse range of mineral origins and varied applications, often representing composite materials or manufactured items where the mineral component is key but not solely defined by a single mineral type.

Within Heading 6815, further distinctions are made to refine classification. Subheadings differentiate between articles primarily composed of carbon fibers and those made from peat. The residual "Other articles" subheading captures the vast array of remaining mineral-based items not otherwise specified. This hierarchical structure allows for precise classification based on the dominant constituent material or specific processing, ensuring accurate tariff application for goods ranging from advanced composite materials to more common peat-based products.