* Colorless/White: This is what most people think of, but even "colorless" diamonds often have a slight tint.
* Gray: A very common color for raw diamonds.
* Brown/Tan: Also a very common color due to nitrogen impurities. It is estimated that it occurs in 75% of all mined diamonds.
* Yellow: Caused by nitrogen impurities.
* Black: Caused by numerous inclusions of graphite or other dark minerals, or due to graphitization (non-diamond carbon).
* Green: Caused by exposure to radiation, this is a less common color.
* Blue: Caused by boron impurities, this is a rare and highly sought after color.
* Pink/Red: These colors are extremely rare and their exact cause is still debated.
* Purple/Violet: This is a very rare color.
Important Considerations:
* Color zoning: A single raw diamond can have different color intensities in different areas.
* Surface coatings: Raw diamonds can have a surface coating that affects the perceived color.
* Inclusions: The type and density of inclusions can influence the overall color.
While colorless, gray, brown, and yellow are more common, the other colors are rarer and often command a higher value, especially if they are vivid and evenly distributed.