Colorless: May indicate anemia.
Red or deep pink: Can indicate a tendency to poor peripheral circulation.
Blue: Blood may not be receiving adequate oxygen due to respiratory disorders, cardiovascular problems, or lupus erythermatosus.
White, crumbly, soft: May be a result of a fungus infection.
Half white/half pink: May indicate fungal infection or, more seriously, kidney disease.
Small white patches: Usually a sign of injury to the nail matrix.
Purple or black: Usually due to trauma, or may also be a sign of vitamin B12 deficiency. A brown or black streak that begins at the base of the nail and extends to its tip could be a diagnostic clue to a potentially dangerous melanoma. See your health care provider.