A common misconception is that real jade only comes in light green. While indeed green jade is the most common and also most sought after, there are also other natural jade colors like red, yellow, lavender, black, and even white.  The difference in colors doesn’t really affect the quality of the jade and doesn’t really affect the authenticity, but since green jade is more in-demand, it tends to be more expensive. Also, different jade colors should not affect hardness and density (or else, it might be an imitation).