The colour is called light steel blue and the codes are,
for black I put in the rgb for licorice 26,17,16 but used the hash of 000001
when using black you can set the rgb value of the color picker box to 0,0,0 and you get patriot smoke for crew as well
Also it is possible to get black chrome by having a crew chrome car and changing the pearlesence on it . it will take the crew color under the chrome and change it to black
pretend this is white : 000000, rockstar wont allow that so we change it to 000100 and rockstar allows that , BUT it wont be white anymore , it will just be like a very very very light coloured yellow or something.
if it looks blue at one point and purple at another it changes in my book, but yes it does have to do with the light. basically a single color with a natural pearl. there is about 3 or 4 blue purple colors that do it. The site I usually use is down ATM other wise I could list what I've tested http://color-names.hex-code.com/