The Very Highest Quality Gemstone Information...

DispersionBack to A - Z IndexChard 24 Carat Home Page

Dispersion is an important optical property of any gemstone. It is what causes the "fire" seen in many stones including diamond. Expressed simply it is the ability of the stone to split white light into different colours. Naturally the technical explanation is a little more complex.

The divergence or spreading of the different coloured rays of a beam of composite light when refracted by a prism or lens, or when diffracted, so as to produce a spectrum, especially in reference to the amount of this dispersion. (O.E.D.)
The power of a transparent medium to separate the spectrum colours.the figures being usually the result of the subtraction of the figures of refractive index for the red ray ("B" line at 6867Ä.) from the figures of the refractive index for the violet ray ("G" line at 4308Ä.). (Gemmologist's Compendium by Webster)

Dispersion is the difference between the amount of refraction of different colours of light. White light is actually composed of light of all different colours. A highly dispersive material will split light strongly into its component colours to give a "prism" effect showing a "rainbow" or spectrum.
Dispersion is often know as "fire".
Diamond owes most of its beauty to its high dispersion, whereas white sapphire, with low dispersion tends to look "dead" or glassy.

You may wish to visit some of our other pages:-

Gemstone Characteristics
Hardness - Moh's Scale
Refractive Index
Specific Gravity or Density
A to Z of Gemstones the Lowest Possible Price

32 - 36 Harrowside, Blackpool, Lancashire, FY4 1RJ, England.
Telephone (44) - (0) 1253 - 343081; Fax 408058; E-mail: [email protected]
The URL for our main page is:
Web Design by Snoop