Q's very informative post prompted me to do more thinking and searching for the origins, meanings, and usages of terms that I referred to in my admittedly mostly off topic post to this thread.
So this post is going to be largely off-topic too.

Click here Pinky for a 1949 movie about a very light skinned Black girl who passed for White. In this movie the African American woman who 'passes for White' is named "Pinky".

This movie is sometimes confused with the 1959 film Imitation of Life
Within 10 years, the theme of the Misfortunate Mulatto {well actually Quadroon} is still used as a tear jearker but in that Imitation of Life* is given the more convention name of Sarah Jane.

*Get it? The light skinned Black woman who is passing is only imitating life, not really living it...

Skin color nicknames for African Americans may be considered derogatory or may be acceptd as a descriptor with no negative or postitive valuation. For instance, I would suspect that those very light skinned Black males or females who were {are} called Casper, Ghost, or Whitey {Whiteboy}, usually don't like it. Of course, just as 'Tiny' could be used as a nickname for a tall person, it is conceivable that "Casper" has been used as a nickname for some Black person who is very dark skinned.

An article in a current Hip-Hop magazine showcases a very light skinned new rapper by the name of Whiteman. The article mentions that "Whiteman" was this rapper's street name and was given to him as his Hip-Hop tag name by his friend.

I find the information about 'Ginger Blue' that Q provided to be of great interest. I may be wrong about the meaning of "Ginger Blue" as that was only a guess on my part. The entire "Walk chalk" verse that I cited may have been purposedly 'buried' as an aside as a second verse of a song that obstentable would not be thought to have anything to do with encouraging people seen as dangerous themselves [i.e. Black people in general, and Black men in particular], to be extra careful, and to perservere inspite of whatever might befall them..

When I guessed about the referent "Ginger Blue" I was particularly thinking of references to Black people being "so black they are blue' or being considered to be "blue black". I know that I have read about a Black male being called 'Blue' but can't find the reference now..Given the strong stigma against dark skin that Black Americans and other Black people have adopted from Whites, I would imagine that a Black person would usually consider it to be an insult to be called "Blue". However, the nickname "Plum" {given to a very dark skinned Black male or Black female because of their dark skinned color} is usually not considered as a put down.

Another nickname that connotes dark skin is "Smokey", but as in the case of the R&B singer/songwriter Smokey Robinson, that nickname can mean just the opposite.

With regard to the phrase "Red Bone", three famous African Americans who were given that nickname were comedian/actor Red Foxx, religious leader/activist Malcolm X {Detriot Red}, and contemporary Hip-Hop artist, Redman.

Perhaps ironically {and perhaps purposely}, "redbone" is the name of a breed of coonhounds [dogs that were trained to hunt racoons}.
"Coons" was a common informal term for Black people [used by some Blacks and some Whites in the past}. It should be noted that this term would be considered Highly Offensive if used today.
See this quote from this website Redbone breed of dogs

"Years ago most coon hunters who owned a red dog of unknown ancestry, but proven ability in tracking and treeing raccoons, called his dog a "Redbone". Then a few serious breeders who were devoted both to the breed and the sport began a campaign of selective breeding to produce a hound with the necessary characteristics to make a superior coonhound and which would breed true to type in color and conformation."

Also see this quote about the history of the African American dance,The Cakewalk":

"The Chalk Line Walk as it was originally known in 1850 in the Southern plantations and became very popular from 1895-1905 with a resurgence around 1915. It originated in Florida by the African-American slaves who got the basic idea from the Seminole Indians (couples walking solemnly). Many of the special movements of the cake-walk, the bending back of the body, and the dropping of the hands at the wrists, amongst others, were a distinct feature in certain tribes of the African Kaffir dances.

The Breakdown and Walk Around were a Minstrel parody, mixed, which later was to be named the Cakewalk was one of the main sources of the Chalk Line Walk. These "Walkers" as they were called, would walk a straight line and balance buckets of water on their heads. Over time the dance evolved into a exaggerated parody of the white, upper class ballroom dancers who would imitate the mannerisms of the "Big House" (or masters house) with such dignified walking, bowing low, waving canes, doffing hats, in a high kicking grand promenade."

-snip-

For more on this dance see http://www.streetswing.com/histmain/z3cake1.htm

(Sorry, but for some reason, I can't hyperlink to that very informative site}.