Love of colour is a natural instinct. Every individual has his own choice and liking for colour. A beautiful fascinating colour is anybody's choice selection. The name natural dye covers all the dyes derived from plants, insects and minerals, i.e. derived from natural resources. Natural dyes with very few exceptions are non-substantive but must be used in conjunction with mordant. The first fibre dyes were already used in prehistoric times after the last ice age, around 1000 BC. They con- sisted of fugitive stains from berries, blossoms, barks and roots. They were early examples of so-called direct dyes. Historically, natural dyes were used to colour clothing or other textiles, and by the mid-1800s chemists began producing synthetic substitutes for them. By the early part of this century only a small percentage of textile dyes were extracted from plants. Lately there has been increasing interest in natural dyes, as the public becomes aware of the ecological and environmental problems related to the use of synthetic dyes. Natural dyes can be classified in various ways. The earliest classification was according to alphabetical order. Later classification was based on chemical structure. In the colour Index the dyes are classified according to chemical constitution as well as major application classes. Natural dyes form a separate section. In this section the dyes are arranged hue-wise. The number of dyes in each hue is given in the adjoining table. Some dyes produce more than one hue.
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