Limitations on Identifying Stamps
Please use care and caution when using the information we present to you here.
Most of the time it is not possible or practical to check and confirm the sellers' identifications and claims of the stamps they offer for sale, and so it is entirely possible that some stamps are mistakenly identified as something other than what they are.
The second problem, which builds on the first, is that you shouldn't use the images you see here - even if correctly identified - as a basis to help you identify your own stamps from a color point of view. These images have been scanned by a huge number of different people, with different scanners, and different settings. This means that the colors are not necessarily correct. For example, a green stamp that one person scans might end up looking yellow, but when a second person scans it, it might end up looking blue!
It gets worse. Take the same green stamp, for example. Maybe a third person also scans it and gets the colors exactly correct. But, wait, there is still more opportunity for error. Perhaps your screen is too "warm" or too "cold" - and this can change the color tint again without you even realising it.
Also, realise because of different people scanning at different times and with different equipment and settings, if you see two images on this site for two similar stamps where the main difference between them is some sort of mysterious change in color - eg, one stamps is described as "blue" and the other as "slate blue", do not use the differences in colors you see in the scans as a basis for understanding what the difference is.
And, it gets still worse. Maybe a stamp has faded from its original color - someone left it out in the sun, perhaps. This will change its color tremendously.
And it gets still worse again. Maybe the stamp, when it was being printed on a four color printing press, wasn't given the perfect color it should have, and maybe to start with, it was freshly printed with a slight color change, which then became worse by fading, and then became worse again by scanning, and then became worse still by your monitor! Wow.
If you are trying to show the difference in color between two stamps, you should scan both stamps at the same time, so that way the comparative color difference can be seen. If you have two different shades of green, then even though your scanning setup might bias all green colors more to the red side of the spectrum, at least the relative difference between the two pieces can be seen in the same scan.
The best, closest thing to a set of color "standards" that we've seen - and it is far from good and very imperfect - is the Stanley Gibbons approach. They use a standardised set of color strips and standard descriptions. If you buy a set of their color strips and use their catalog, this is about the closest you will ever come to having standard colors. Professional color workers will recognise this as akin to the Pantone PMS system - a great idea.