What can the color of a mineral determine?
Color can tell help determine the properties of a mineral because each element absorbs wavelengths at a different rate, causing a color specific to that element. Even though color is generally the first thing we notice about a mineral, it is not always the most reliable diagnostic property. Very small amounts of an element can influence the color of a mineral making it appear to be one thing when it is really something else.
An example of this is pure quartz vs. purple quartz.
Both of these minerals are quartz, however the purple quartz contains a very small trace amounts of an element that gives it a purple hue, without changing its quartz properties.
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