According to color, the following varieties are recognized.
Achroite: (Greek – without color) colorless or nearly so. Rare
Rubelite: ( Latin reddish) pink to red, sometimes with a violet tint: ruby color most valuable
Dravite: (after Drave in Austria) yellow brown to dark brown.
Verdelite: (Italian/Greek – green stone) green in all shades, most common of all tourmalines. Emerald color most valuable.
Indigolite or Indicolite: blue in all shades.
Siberite: (after finds in the Urals) lilac to violet blue. Sometimes used as synonym for rubelite.
Schorl: black, very common. Rarely used for jewellery. Name derived from old mining term.
Uni color tourmalines are quite rare. Most crystals have various color shades or even different colors. Often there is layered color. Brazil produces stones with a red interior, inner skin white otter skin green. The South African tourmalines are green inside and the outer layer is red. A tourmaline with red inside and green skin is sometimes called “watermelon”. The nuances and colors are particularly effectively shown when slices of cross-section are polished.
Tourmaline cat’s eye exist in various colors, but only the pink and green varieties is the chatoyancy strong, caused by inclusions of foreign crystals. Some tourmalines show a slight change of color in artificial light.
The most desired colors are pink, intense green and red. Because of the strong pleochroism, the stone must be cut so that the table lies parallel to the main axis.

*Info by Walter Schumann “Gemstones of the World”