For the Silver Thistle tartan, STA has a “picture” at the following url:

http://www.tartansauthority.com/tart...histle-fashion

The corresponding "picture" on the Register shows

http://www.tartanregister.gov.uk/tar....aspx?ref=3789

They both have the same threadcount, but on at least two computers the Register shows the color Oxford as purple and the STA as blue. I know that computer displays only approximate true color, but they are not usually this far off. Will someone please explain the difference? Thanks.