The origins of the pigment carmine date back a long way. It is considered one of the oldest organic pigments, and was first discovered in the early 16th century, when the Spanish invaded Mexico. They were in awe of the deep red painted fabrics and face paint of the Aztecs. It came to light that this brilliant red colour was derived from cochineal insects that lived on cactus plants. The Spanish decided to bring this 'Spanish Red' colour to Europe by planting cactus plantations in Spain, so that the cochineal insects could be allowed to flourish. For some time, Spain had a monopoly on the market for manufacture of carmine pigment, until other countries discovered the techniques involved to make it themselves. How was the colour made? Carmine is produced from the female of the cochineal insect species - females are thought to outnumber males by 200 to 1. These scale insects and their eggs live on cactus plants, and are brushed from the plant and left to dry in the sun. Once dried, they are boiled in order to extract the carminic acid, which makes up around a quarter of the insect's weight. This is naturally present and helps to protect them from predators. This acid is then treated with an alum solution to precipitate the red colour. Other substances such as citric acid, borax, stannous chloride or gelatine may be added to regulate this process. Lime is often added to create a purple colour. The quality of carmine is affected by temperature and sunlight. It is estimated that around 70,000 of the insects are needed to make just one pound of cochineal pigment. Not surprisingly, for some time, it was considered one of the most expensive pigments. Other names for carmine include crimson lake, cochineal or natural red 4. What was carmine used for? Whilst carmine was used in ancient times to dye fabrics, it was only from the 18th century, that artists started using it, especially in watercolour paintings. The colour had a reputation for poor lightfastness, however. It is made today using synthetic pigments, and is widely available from art suppliers such as http://www.jacksonsart.com. Other uses of carmine As well as paints and crimson ink, it was also used in the manufacture of artificial flowers. More commonly, it has been added as a dye to food and drink, such as pastries, yoghurt, juices and ice cream. Cosmetics such as eyeshadow and lipstick also use carmine to create a red colour. It can also be found in some medicines. Carmine can cause allergic reactions in some people, so there has been increasing pressure for food and drug manufacturers to list carmine on the labelling of a product. Although it has not been banned in food, according to the Food Standards Agency (AUTHORITY URL: http://www.food.gov.uk/science/additives/enumberlist#Colours) it is subject to quantitative limits and has to be used in conjunction with appropriate EU legislation. Since 2012, medicines containing carmine have been manufactured using a synthesised version of carmine from plants, rather than the insect derived form.