Lester Kong's Contemporary Record Label

I recently purchased Shelly Manne at the Black Hawk vol. 1-4. All are yellow labels. All are stereo. But there are differences in the labels and the covers. I expect some may be originals and others are reissues. Some of the dead wax info looks hand written. I also have a stereo copy of vol. 1 that is a black label. It is thicker and heavier than the yellows. Anybody out there know the history of Contemporary labels? Thanks
The Black label is the only original pressing.All Stereo issues on Contemporary Label are black.They went out of business in mid 60s,were revived in 70s.Fantasy repressed many titles,but these should be readily apparent by OJC (Original Jazz Classics) prefix to catalog #.They often have Fantasy name and or address on Cover.If "P.O. Box 2628 Los Angeles" appears on cover it is a re-issue(though not a Fantasy re-ish)I looked at some dozen Manne LPs I have on Contemporary.All had machine stamped matrix #s.Only one was thinner vinyl,it also had a small black boxed logo(a CR ) below the MP in Contemporary on the label.This LP is certainly a re-ish.My feeling is that because they went out of biz in early 60s there is no reason any original would not be on nice thick wax.All the originals I own are thick.Not just Shelly Manne,but Prince Lasha,Rollins etc.