|Serway, Raymond A. Faughn, Jerry S. College Physics 6th Edition. Publishing Alternatives 2003: 692.||
|Structure Probe Inc. Fused Quartz used for SPI Supplies Brand Quartz Slides and Cover Slips. SPI Supplies. 22 May 2005.||"Index of refraction: 1.4585"||1.4585|
|Philip R. Bingham, Kenneth W. Tobin, Marylin H. Bennet, Pat Marmillion. Preliminary results for mask metrology using spatial heterodyne interferometry [pdf]. 2003.||"The index of refraction for chromium at a wavelength of 532nm is 2.9+j4.44, and the index of refraction for quartz is 1.55 at 532nm  …  CRC Handbook of Chemistry and Physics, 67th Edition, 1986-87, pp. E377-E392."||1.55|
|Index of Refraction. Microsoft Encarta Online Encyclopedia. 2005.||
Quartz is silicon dioxide (SiO2) and is a naturally occurring crystalline material. It is made up of sand but comes in many different grades as it is far from a "unique material." Many of the different forms contain various different additives and impurities which, as one should expect come in a variety of different prices. The highest grade quartz is used in the electronics industry typically for wafer carriers, flanges, and a variety of other high maintenance optical applications. Fused quartz is a man-made material manufactured from the same starting material, SiO2, which is then heated, melted and after various processes to ensure its purity, is quenched to the amorphous state and formed into large blocks. An index of refraction is a value calculated from the ratio of the speed of light in a vacuum to that in a second medium of greater density. The Index of refraction of quartz is calculated to be 1.458, this value is a function of temperature, pressure and wavelength of light and has no unit since it is a ratio.
Gil Fishman -- 2005