Precious-Opal and/vs X-Ray Diffraction

AI Thread Summary
The discussion centers on the exploration of how precious opals produce their unique play-of-color (PoC), particularly the contra-luz effect, which involves transmission rather than reflection. The author is attempting to bridge their background in math and computer science with the complexities of optics and X-ray diffraction to understand this phenomenon better. They express difficulty in correlating X-ray optics with the visible spectrum relevant to opals, particularly regarding the Bragg equation and its applications. The author seeks insights from knowledgeable individuals in X-ray optics to validate their findings and clarify instances where X-rays are reflected rather than transmitted. This inquiry highlights the intersection of materials science and optical physics in understanding opal characteristics.
PMH
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(My (old) background is math & computer science. I've long loved (mostly) precious opals - for their esthetics, lapidary potential, synthesis (which I've done), and how the play-of-color ("PoC") is produced.)

I recently did another couple of passes on the latter in the process of trying to figure out how the contra-luz flavor of PoC is produced.
(Contra-luz is transmission PoC rather than reflection PoC.)

I was trying to do the research efficiently, which came down to decisions on how much I had to go back to learning ... optics? ... from scratch all the way up to what I need for this effort -vs- trying to understand as much of it as I needed to just by trying to make more & more sense out of material that's intended for people who have such a background.


One of the places I happened into is X-Ray ~optics~.

But it was hard to make the correlations betw/ this range of wavelengths and the visible (for opals).
...even though, put that way, it sounds like it should be trivial.

Problem was that uses of X-Rays tend to be about their transmission - whereas for opal, I was trying to get from reflective to transmissive.

I couldn't see, eg, how the Bragg equation (or its derivations) could (& should) be used for the transmission case.

Maybe I should admit that I avoided reciprocal space.
(& hope to be able to continue to do so for this research, although I could be convinced otherwise, I guess)

Surely there are cases where X-Rays are reflected rather than transmitted by the diffraction, but I never did find out what those cases are.
(so that in itself would serve pretty well as the official question for this thread)
 
Science news on Phys.org
Google "photonic bandgap material" and "artificial opal". You should find infinite relevant links to choose from.
 
Thank you, Andy.

Now I'm sorry that I didn't make it clear that that's exactly what I have been doing - for many months.

In fact, I'm pretty confident that I've figured out the answer; what I want is to check it via seeing how actually knowledgeable people in the field of X-Ray optics treat it.
(as opposed to me - not you)
 
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