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Homework Help: Why do diamonds sparkle?

  1. May 25, 2004 #1
    I was asked by someone, "Why do diamonds appear brilliant to the eye?" I am having trouble coming up with a solid answer. All I could find out was it has a high index of refraction of about 2.42. I need some assistance with this.
  2. jcsd
  3. May 25, 2004 #2
    basicaly because of how much light is refracted. The diamond will redirect the light all through out it which gives it the so called fire. A higher index of refraction means more reflected light. I belive the forumla is n is congruent to c over v phase
  4. May 25, 2004 #3
    Exactly. The term for it is cleavage.
  5. May 29, 2004 #4


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    two words: bling bling
  6. May 29, 2004 #5
    Well i Certainly Didn't understand what you said but i will explain what i know.

    Basicly when light moves through the diamond which does have a refactive index of 2.42 light refracts (bends).

    Light is made up off all the diferent colors Red Orange Yellow Green Blue Violet Indigo .

    When light moves through an object the light is bent (towards the normal which is perpendicular to the surface its hitting), but, all the different colors bend different amounts, Most of the time it isn't noticable, because the refractive index is low. But in a diamond, where the refractive index is high, the different colors bend enough to break apart the white light into a rainbow of color.

    When the light exits the object it is bent again ( away from the normal) and because most cut diamonds have many diferent sides light is bent in many different directions giving it a sparkly effect.

    The only forumla you need to know is N1/N2 = SIN I / SIN R
    Where N1 = refractive index of first substance and N2 = Refractive index of second substance, I = Incidence and R= Refraction. You can just transpose this forumla around to get what you want.

    Of the top of my head I think Red is refracted the most and indigo is refracted the least.
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