Colour is least reliable property to recognise mineral in field. but is best for studying and recognising mineral in lab under Polarized light microscope (PLM). <br /> let us take a simple example of quartz and calcite both have nearly same colour range so just by observing colour you can not give a guess but by applying different field techniques at same time we can distinguish them as calcite can be scratched by nail but quartz will not be scratched. <br /><br /> (Allah Knows the Best) <br /><br /> One interesting thing is that colour is most deceiving thing in this world. About 90% of frauds are done by colours. it I think I need not to explain it. :-) <br /><br /> CHEERS
Color.
The observable color is the least dependable method of mineral identification.
The streak, or color of a mineral's powder, represents the true color of a mineral without the effects observed in a hand specimen due to impurities, inclusions or differences in light reflection.
Believe it or not color is the least reliable identification method for a mineral. While it can be very helpful when used along with other types of identification tests, color alone proves nearly useless. This is because several different minerals can have the same color or one mineral can be several different colors. Generally this is due to the varying chemical compositions a single mineral can take on. For example, iron, depending on its oxidation state, can cause the same mineral to be several different colors, leaving the examiner with a large list of possibilities. Also, in another example, there are hundreds of minerals that are known to be green so again the possibilities are endless.
It's not reliable because there can be more than one mineral with that color
Specimen color is the least reliable method of mineral identification. Better characteristics are streak, density, and crystal structure.
A mineral specimen's color can be affected by radiation or impurities. A better method would be to use the mineral's streak, the color of the mineral in powdered form.
Color is the least reliable of a mineral's characteristics used in its identification.
Color.
Color
The observable color is the least dependable method of mineral identification.
The streak, or color of a mineral's powder, represents the true color of a mineral without the effects observed in a hand specimen due to impurities, inclusions or differences in light reflection.
The streak, or color of a mineral's powder, represents the true color of a mineral without the effects observed in a hand specimen due to impurities, inclusions or differences in light reflection.
Believe it or not color is the least reliable identification method for a mineral. While it can be very helpful when used along with other types of identification tests, color alone proves nearly useless. This is because several different minerals can have the same color or one mineral can be several different colors. Generally this is due to the varying chemical compositions a single mineral can take on. For example, iron, depending on its oxidation state, can cause the same mineral to be several different colors, leaving the examiner with a large list of possibilities. Also, in another example, there are hundreds of minerals that are known to be green so again the possibilities are endless.
It's not reliable because there can be more than one mineral with that color
the color is the least reliable source!
The powder indicates the true color of the mineral and is an aid in mineral identification. That can also be called a streak.