One of many postcards of Silver Bay from Detroit Publishing. In the late 1890’s, the company obtained the rights to a Swiss process for converting black-and-white photos to color prints using lithographic stones. A separate stone was used for each color, from four to 14 stones depending on the complexity of the photo. Cheaper methods eventually put the company out of business. Of their Silver Bay postcards I have seen, the postmarks date from 1907 to 1917.