Van Dyke browns or Brown prints are quite beautiful and it is a technique to which I have devoted some considerable time. With most of the historical processes I have experimented with, image permanence has often been an issue, often resulting in modern technological techniques to arrest the image. However, with Van Dyke Brown that has not been the case. Some months in to my experiments with this process, I put one out on a table in the garden on a bright August day (England). The sunlight was ferocious and I put a rock on top of it and left it for a few days. The intensity of sunlight was sufficient to fade an average newspaper in this time. When I removed the rock I could see no discernible difference where the rock had been. I was most impressed and hence continued to experiment with this process.