It is with great sadness I'd like to announce Dr. Hanneman passed away on December 12, 2020. His legacy will live on forever!
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 Post subject: Blue Minerals:Exploring Cause & Effect, Rocks $ Minerals,
PostPosted: Tue Jan 26, 2016 12:53 pm 
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Joined: Thu Sep 25, 2008 10:33 am
Posts: 833
Location: Mars PA
The final part of the citation is 91:1, 61-77.

Barbra asked me to review this article so here goes.

The article is well written with the stated objective of bringing the subject of color in minerals to the public without unnecessary technical terms and graphs. I use the word color rather than blue, because there is relatively little that is stated about blue in the article that couldn't have been made for all colors. But there is a danger in trying to frame complex technical issues in creative vernacular. This is the introduction of ambiguity into definitions that have been constructed with care, using words that possess a very restricted definition. Light and its interaction with matter is both complex and at times so counter intuitive that even today we still need two models for it, one based on its behavior as a particle and one as a wave.

On the whole, the authors do a good job with their attempt to be approachable. There is only one scientific misstep that is important to me, and that is saying that the degree Kelvin associated with the different tints of white light comes from the temperatures of the filament of an incandescent light rather than the temperature of a hypothetical entity called a black body radiator. Perhaps this is being picky, since both the real emitter and the hypothetical one are closely related, but I think it would have been better to not go there, in such a brief article, than explain it incompletely. Most digressions added a personal touch to the article, but I felt that introducing a diagram from an old article that was incorrect and then explaining why, was a waste of precious space.

The most interesting part of the article was why water is blue. I had never looked into the matter and it is different. The most unsatisfactory part of the article was on color change. Writing that the eye-mind is "tricked" by the subtle changes in the light coming from a color changer material under different luminants is hardly enlightening. Especially since I know that the scientific literature holds a much better explanation for the nonlinear behavior of the eye-mind. I also feel that the quote extracted from a paper by Dr. Nassau needs more support to make it satisfying and complete.

A final petty point on a paper that is well worth reading, is the lack of any pictures or real discussion of blue tourmaline (Indicolite is noted, but comes up missing in the cited illustration). It helps color my world.


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