Quote Originally Posted by auld argonian View Post
I suppose that it would be a noble experiment for someone with a few spare swatches to mount them on a board and put them outside in the sun and snow and wind and rain for a year and see what happens...
It has been done. If I remember correctly, Modern colours dyed with aniline dyes fade to Ancient tones when left in the sun for one year. The information is likely here somewhere. http://www.scottishtartans.co.uk/research.htm

Quote Originally Posted by Jock Scot View Post
So,I wonder, are we looking at" modern weathered" colours from the mills of today, that are an "interpretation" and an "approximation" of how colours might, could, maybe, perhaps, but not necessarily look like after 200 years of use? Or, are we looking at a cunning plan to offer another colour scheme to sell more tartan?I really don't mind that, it is business after all, but I do like to know these things before parting with hard earned cash.
I'll bet there's some of both. Scheming to sell more tartan cloth the weavers interpret new 'conditions'. it makes sense too. Ancient colours were only about 30 or 40 years old and becoming quite popular. Why not take the next step and 'stress' the colours even further?