where do the colours for human products (paints/fabric/dyes...etc) come from?

Answer 1

"Natural pigments include various clays, calcium carbonate, mica, silicas, and talcs. Synthetics would include calcined clays, blanc fix, precipitated calcium carbonate, and synthetic silicas."

http://en.wikipedia.org/wiki/Paint#Pigment

"Naturally occurring pigments such as ochres and iron oxides have been used as colorants since prehistoric times."

"Pigments from unusual sources such as botanical materials, animal waste, insects, and mollusks were harvested and traded over long distances."

"Tyrian Purple is a pigment made from the mucus of one of several species of Murex snail."

" The only way to achieve a deep rich blue was by using a semi-precious stone, lapis lazuli, and the best sources of lapis were remote."

"Spain's conquest of a New World empire in the 16th century introduced new pigments and colors to peoples on both sides of the Atlantic. Carmine, a dye and pigment derived from a parasitic insect found in Central and South America, attained great status and value in Europe. Produced from harvested, dried, and crushed cochineal insects, carmine could be used in fabric dye, body paint, or in its solid lake form, almost any kind of paint or cosmetic."

"The Industrial and Scientific Revolutions brought a huge expansion in the range of synthetic pigments, pigments that are manufactured or refined from naturally occurring materials, available both for manufacturing and artistic expression. Because of the expense of Lapis Lazuli, much effort went into finding a less costly blue pigment."

...

http://en.wikipedia.org/wiki/Pigment#History_of_pigments

Answer 2

I would highly recommend the book A Natural History of the Palette by Victoria Finlay. The woman who researched it traces each color back through history. For instance there was a paint called Mummy Brown, that was made from dead mummy parts in Egypt, ground up and liquefied with some other stuff. Later it was getting hard to steal these preserved people from egypt, so grave robbing in England kept the paint being marketed a little longer. Some of the great masterworks of Europe have this pigment in them. My favorite story was of an artist who learned that Mummy Brown was actually made up of corpses. He was so horrified, he buried his tubes in the back garden and held a make shift funeral.
Apparently Van Gogh's paint dealer was an ex pirate. When he was not paid right away for his paint, he substituted a more cheaper volatile substance. It was many years later that collectors discovered that the white roses Van Gogh is so famous for were once red.
You can spend hours learning about some of these great histories of colors, paints and dyes. The green in Napoleons wallpaper is suspected of causing his death . His death was a mystery at the time, but there were lots of folks that knew the particular green color of the wall paper was known to be very toxic, but people were reluctant to give up the nice colored wall paper for health.
What makes this all the better is how much more appreciation I have for the paint I buy today, and the ease in which I can buy it.