SCANDINAVIAN MINERALS
Information on the colour rendering of minerals.
Colour Rendering Index (CRI), previously called Ra-index.
The CRI scale ranges from 0 to 100, where a higher value indicates better color rendering.
A CRI of 100 represents perfect color rendering, equivalent to the sun.
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The visible light wavelength from the sun has CRI index 100.
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The artificial light indoors has colour peaks in 3 wave lengths,
blue, green and orange-red. |
LED lights today can produce CRI around 90 or better. CRI without these three peaks.
CRI is a quantitative measure of a light's ability to reproduce the colors of objects faithfully in comparison with an ideal or natural light source.
There are a number of minerals that exhibits a different colour rendering depending on the lightning quality.
One good example is the mineral Strengite from Leveäniemi Mine, Lappland, Sweden.
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Strengite in indoors lightning CRI-85.
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LED light with CRI-95 and better.
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All Scandinavian Minerals pictures are CRI-95 to 97 depending on what lightning source is selected for a certain mineral.