The colour tan is to be found everywhere. In fact it is an umbrella term for lots of colours. Dark tan, light tan, English tan and many more. They all have one common origin. Making leather.
Somewhere back in the mists of time a skin got left in one of those forest puddles of water where lots of vegetation had turned the water brown. To the astonishment of a careless individual it did not rot away in the way a raw skin normally does, but came out brown and stabilised against the bacteria that would normally have devoured it all. And it was brown.
So that careless individual all those Millennia ago had in fact discovered what we call today vegetable tanning. Vegetable tanning has been the backbone of nearly all the leather made in history of the world. If you drink tea you are already an expert. In putting tea leaves into warm water you leach out a generally brown material in which is to be found a quantity of tannin. This is exactly how the tanner has always obtained the tannin to make leather.
It is quite possible to use tea to make leather but over the years tanners identified the trees and plants, and the part of them, that contained good quantities of the right type of effective tans. In much of Europe chestnut predominated, in England oak was more common, in Russia birch was commonly used along with willow and the US hemlock was common in New England while oak was more used in the south.
After the hair is removed from the raw hide or skin it is cleaned and washed. After a little chemical preparation the hides and skins are then dropped or suspended into a vat containing the chosen tanning material and left for an appropriate time. This is usually weeks but may be months. In the past in Europe for good quality leather a year in the tanning pits was required and still today the few tanners who still specials in oak bark tanning stick to this year minimum rule.
But by adjusting the conditions and the tans used, along with the temperature, high quality leather can now be made in just a few weeks. Some vegetable leathers are now also made by tumbling in an aqueous solution rather than being dropped into pits but to the traditionalist seeing a large Hall full of “tanning pits” remains an evocative sight.
However your vegetable tanned leather has been made it will have a natural “tan” colour which will depend on the type of tannin which has been chosen. If it is black or another colour, that means it has been stained in some way to achieve the desired colour, but natural tan remains a strong favourite.