Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by composition]
6. inorganic material
7. glass (material)
8. [glass by technique]

Anotations

Scope note:

Sheet glass made by floating a ribbon of hot glass on a bath of heated liquid, usually molten tin. The process was developed in 1959 by Pilkington Brothers and is now the world's principal method of manufacturing good quality sheet glass which is clear, flat, with parallel and fire polished sides.