Many people who keep Guinea Fowl like to specialise in one colour whilst others prefer a mixture.
The birds come in a large range of colours, 21 different colours have been identified, they fall into 3 groups, Fully Pearled, (small white dots all over), Partially Pearled, (white dots in some areas), and Solid Colours, (no dots).
Among my birds I have Pearl Grey, Pearl Lavender, Royal Purple, Pearl Buff, Chocolate, Buff Dundotte and White.
Birds can also be Pied, this is when a bird has a coloured back and white front, or sometimes white wings.
There is an excellent colour chart with photographs on the Guinea Fowl International association page, available from my links page.