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How do you describe the color of a mineral?
Color and luster describe the mineral’s outer appearance. Streak is the color of the powder. Mohs Hardness Scale is used to compare the hardness of minerals. Some minerals have special properties that can be used to help identify them.
What is play of Colours in minerals?
A pseudochromatic optical effect resulting in flashes of colored light from certain minerals, such as fire opal and labradorite, as they are turned in white light. Periodic spacings of phases with slightly differing refractive indices act as optical diffraction gratings in these minerals.
How do minerals look like?
Minerals can be identified based on a number of properties. The properties most commonly used in identification of a mineral are colour, streak, lustre, hardness, crystal shape, cleavage, specific gravity and habit. Most of these can be assessed relatively easily even when a geologist is out in the field.
Why do minerals have different colors?
Minerals are colored because certain wavelengths of incident light are absorbed, and the color we perceive is produced by the remaining wavelengths that were not absorbed. Some minerals are colorless.
What affects color of minerals?
Color in minerals is caused by the absorption, or lack of absorption, of various wavelengths of light. The color of light is determined by its wavelength. When pure white light (containing all wavelengths of visible light) enters a crystal, some of the wavelengths might be absorbed while other wavelengths may be emitted.
How do minerals get their colors?
Minerals are colored because certain wave lengths of light are absorbed, and the color results from a combination of those wave lengths that reach the eye. Some minerals show different colors along different crystallographic axes. This is known as pleochroism.
Does every mineral have a color?
Almost every mineral has an inherent streak color, no matter what color the actual mineral is. For example, Calcite occurs in many different colors, shapes, and varieties. But every single variety of Calcite has a white streak. A streak is useful in distinguishing two minerals with the same color but different streak.
Why do the same minerals come in different colors?
In some cases, the color of a mineral may depend on its atomic bonding rather than composition, such as by Diamond and Graphite. Both these minerals have the same are formed from the same material (carbon), yet one is almost always white or very lightly colored, while the other is dark gray to black.