This picture shows three different colored CD 127's embossed "W. Brookfield 55 Fulton St" on the front dome and "Pat April 4 1871" on the back dome. You will note that these are all the standard "knob" dome style in green (far left), blue (middle), and a nice blue-green (far right) colors. There are also two slightly different green shades which I will show in the next picture. I have found the blue or blue-aqua colors are the most common. The green are uncommon, but I feel the blue-green is a rare color. I've found maybe 8 to 10 of the April 1871's in green and only three of the blue-green color. These were all traded into the hobby many years ago.