Chevron amethyst or banded amethyst as this type of quartz tends to be known in the UK is the mineral amethyst. The colour zoning gives the stone a completely different appearance.
Colour zoning which is common in amethyst occurs when different shades of colour are present within the same crystal. Banded amethyst which is the most extreme example has sections of white quartz. The chevron-like patterns often present are the reason it's called 'chevron' amethyst.
This large and beautifully polished banded amethyst sphere comes from South Africa. It is heavily included and has one or two very minor indentations.