For someone interested in color I recommend contacting your local stamp club (or APS) and ask for help in getting started in color identification.
Like many, I found out the hard way that some certs are better than others so far as rose-pink is concerned. I sent in a 3-cent cover postmarked Aug 27, 1861 (1st Week of use), and it came back as #65(?). Evidently the "expert" didn't look at the postmark, only judging the stamp by its shade.
Rose pink was the first color, but it happens that not all rose-pink's are primarily "pink" in appearance. Some stamps, as the one I have on cover, have more rose than pink. It is not uncommon for the dominant color in the deeper shades to be rose, and I have several off-cover varieties of this. To the untrained eye this shade appears ordinary, but on careful examination it does not fit in with any of the later printings (rose red, rose lake, rose claret, etc.).
The pale varieties of rose-pink have more pink in them, and this variety is more closely associated with the shade. Upon finding one of these some people believe it to be "Pink," but it pales in comparison with the "True Pink."