Every culture and religious or spiritual path has colors they associate with luck. The Egyptians were no different. They too had colors that meant good fortune. Before we get into talking about tombs and tomb paintings it might be worth while to discuss what the colors meant to Egyptians.
Black: considered one of the most lucky colors by the Egyptians. This association was linked to the black soils left by the flooding Nile. Black was the color of fertility and of the ideas of being blessed. Black was also associated with chaos and unknown/mysterious things because of night time and darkness associated with it. It often makes me wonder what an Ancient Egyptian might call out when he or she stubbed their toe on the couch walking in a dark house. Several gods are associated with the color black including Set, Sobek, Khnum, Hapi, Osiris and Apep. Horus is named the Ruler of the Black Land, ie the Nile Valley.
White: The color of truth and harmony. White is most often associated with Ma'at and the life giving powers of the lotus. White was also the color of the traditional garments of most Egyptians. Egyptologists suggest that the good fortune of white might be related to the way white repels the heat of the sun while black becomes blisteringly hot in the sun. White is also symbolic of the prevention of decay, likely, because of the white wrappings of a mummy. White is associated with Lower Egypt and rulership due to the white crown of the pharaoh.
Red: The color of blood and strength in the Egyptian mindset. It has the dual ideas of being a color of bloodshed and healing. The color is sacred to both Hathor and Sekhmet, both goddesses who went from rampaging menaces of blood lust to kind and caring goddesses. Red is the color of Upper Egypt and the pharaohnic crown of that region. Red is also associated with the desert regions. Set was given the Red Land to rule.
Orange: The color of death and rebirth. Orange is associated with the sunrise and sunset, there fore with death and resurrection of god and mortal alike. Orange is one of the sacred colors of Khephra, the beetle form of Ra, associated with rebirth, resurrection and change.
Yellow: This is the color of Ra, Horus and all the solar deities. Associated, like gold, with the rays of the sun yellow is a color of warmth and comfort. Yellow is also symbolic of power and kingship because of its association with the sun.
Green: The color of fertility and lush growth made green a very positive color in the Egyptian mind. Green was a color associated with many gods of prosperity and plant growth such as Hapi, Osiris, Sobek and Tuaret.
Blue: Blue is a very sacred color with a wide range of meanings. Blue is the most common color associated with amulets and therefore protection. Blue is also the color associated with death. This often makes me wonder if it is related to the blue-ish hue of lips when someone dies. I haven't seen any information to tell me either way. Blue was also associated with death because of the Egyptian belief that the dead passed through the sky. Blue has some associations with lotus flowers which might give it some connection to life or rebirth. It is likely that there were life associations because Tuaret statues are often shown in blue when she is given the duties of protection.
Violet/Purple: I have seen almost no references to purple in my research thus far. I will be sure to look more deeply into this. In fact, I didn't even realize I hadn't read about purple until this post. Good reminder that there is always more to learn.
Gold: The sacred color (and material) of both the sun and the pharaoh. Gold is the color of power, control, destiny and worship. The list of the importance of gold would be a whole article. It might be explained by simply saying gold is the most important color to Egyptian culture and religion.
Silver: Silver isn't often used in Egyptian metal working but there are associations with the priesthood, night and the common people given to silver from time to time. Silver is also related to the ideas of health and knowledge, likely due to the association of Thoth with silver in some myths.
That covers all the basic colors. If you want to know about a color I didn't list feel free to ask. I will do my best to find references and meanings for the rest of the myriad of colors.
On a side note, as I was already asked this via email..... The color associations I listed above are related to the Old, Middle and New Kingdoms. Greeks, Romans and more modern people may have had other associations when they viewed the Ancient Egyptian religion or when a blended religion was created. So, what I have said may not be agreed upon by all practitioners of Egyptian style religions/paths.