Painted by the French Impressionist Pierre Auguste Renoir (1841–1919), Fog on Guernsey recently paid a visit to our lab for cleaning—and it let us in on a charming secret. When we removed the backing board that is attached to the back of the stretcher, we discovered a small colorful postage stamp stuck to the back of the canvas. Sometimes postage stamps are used as a quick, temporary repair to a hole or puncture. But that’s not the case here. A closer look shows that the stamp was issued by the Isle of Guernsey in the amount of 31 pence. And not only that, but CAM’s painting is printed on the stamp!

When the stamp was attached is a bit of a mystery, but since it’s doing no harm to the lined painting, we’re going to leave it as a charming secret to be revealed the next time the painting is unframed.