This is one of my 'Samson' collars. I gave it to this handsome boy to test because he is big and strong and has a track record of breaking collars, and he belongs to a friend who does lots of outdoor things! I think it does have yellow stitching on it when it is not covered in grot.
I also have a new blue leather for the poodle size collars. The new colours are cornflower (white stitching), forget-me-not (yellow stitching), and delphinium (purple stitching). Toy-size collar shown below.
My collars and other stuff are here and here.