Final answer:
Asbestos facings are rarely used as full-face linings despite their heat resistance and noncombustible properties. They are commonly found in three forms: chrysotile, amosite, and crocidolite, and decompose at high temperatures into forsterite and silica.
Step-by-step explanation:
You asked what types of facings are rarely full-face linings. Among the options provided, ceramic, glass fiber, asbestos, and organic materials, it is the asbestos facings that are rarely used as full-face linings. Asbestos has been historically used in various industries due to its resistance to heat and noncombustible nature.
This fibrous material is commonly found in three forms: chrysotile (white asbestos), amosite (brown/off-white asbestos), and crocidolite (blue asbestos).
Asbestos is known for its use in terminal insulation material, brake linings, construction materials, and filters. Additionally, when mixed with cement, its fibrous strands can significantly reinforce the mechanical strength of concrete. However, when subjected to high temperatures, asbestos can decompose, leading to the formation of forsterite and silica.