Raman Spectroscopy

In the Keanu Reeves movie Siberia, Keen-o uses a magic box to tell real diamonds from fake ones. The fake diamonds aren't really fake, they are just as real as the real diamonds. The difference is the fake ones were manufactured while the real ones were dug out of the ground. I think the difference the machine is looking for is the presence of nitrogen - real diamonds have it but artificial ones don't. After rooting around for a bit I found that Raman Scattering is what the magic box uses to detect the presence or absence of nitrogen.

 
Raman spectroscopy has been around for awhile:

The Raman effect was named after one of its discoverers, the Indian scientist C. V. Raman, who observed the effect in organic liquids in 1928 . . . Raman won the Nobel Prize in Physics in 1930 for this discovery. 

In the beginning it was very difficult to observe the phenomena. Lasers have made it much more practical. Let's let YouTube show us how.


Intro to DIY Raman Spectroscopy
Applied Science

Not the smoothest exposition, but he covers all the major points.


Homemade Raman Spectrometer: Diamond
toc1955

This one is so short that you won't have time to read the text. Remember the space bar is your friend. It's here because he has some good graphs of the results.


Basics and principle of Raman Spectroscopy | Learn under 5 min | Stokes and Anti-Stokes | AI 09
Practical Ninjas

Mr. Ninja is not a native English speaker. In this case subtitles are your friend.

Lastly, if you want one of these magic boxes, you can buy one from Stellar Net though it will cost you a pretty penny.

StellarCASE-Raman - Portable Raman System for Material Identification | StellarNet, Inc.