Main Page | See live article | Alphabetical index All-silica fiber is an optical fiber composed of silica-glass core and cladding. Refractive index of the core glass is higher than refractive index of the glass forming the cladding. The cladding of an all-silica fiber shouldn’t be confused with the polymer overcoat of the fiber. Synonyms: all-glass fiber, silica-silica fiber. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.