Black:
Sadness, evil, mourning, overcome fears, depression, loss, confusion, discord, to curse or break a curse

Blue:
Subduing, calmness, serenity, spirituality, devotion, tranquility, understanding, patience, health

Brown:
Non-specific, untangling, general good, magnetism, hesitation, uncertainty

Green:
Luck, money, wealth, financial success, fertility

Orange:
Peace of mind, good health, courage, vitality, spirit, encouragement, adaptability, stimulation, attraction

Pink:
Success, promotions, conquering bad influences, honor, love, morality

Purple:
commanding, compelling, overcoming enemies, power, healing, tension, ambition, business progress

Red:
Love, attraction, friendship, well-being, life force, strength, health, vigor, sexual love

White:
Truth, purity, spiritual strength, sincerity (if you're using candles in your ritual, adding a white candle with any other candle color will enhance that other colors' powers)

Yellow:
Dispell evil, drive away jealousy and envy, calm tensions, attain intellectual power, attraction, persuasion, charm, confidence

Gray:
Cancellation, neutrality, stalemate

Greenish Yellow:
Sickness, cowardice, anger, jealousy, discord