This is the Margaret stitch taken from the book "Wessex Stitchery" by Gay Eaton. Unfortunately this book is long out of print and only available at extortionate prices from Amazon Used Books. I have taken a scan of just this stitch and you can follow your own colour scheme. One hint is that the placement of the colour should be as random as possible.
I often use Wessex Stitchery for needlebooks and hussifs that are to travel overseas as gifts because Gay Eaton is a fellow New Zealander and was responsible for the revival of this old technique. Here's a photo of another style - this is called Essex Stitch - which I made into a needlebook for an exchange about three years ago
And also a close up of the Margaret stitch.
I hope that is helpful - if you need anything else please email me and I'll do my best to answer.
Have a good night everyone.