Live rock color??

[fagundespavinp3]

I have a few pieces of live rock in my 10 gal tank and one of the pieces is getting a large amount of gray color in spots and was wondering if this will stay this color? Will it change to purple? And

is it good or bad that it is this color. I have 4 pieces of LR one is beautiful mix of purple,burgundy light-green and pink and the other 3 are white with little spots of the dark burgundy purple.

 

[fagundespavinp3]

 

[booth2010]

I think I have read before that it could be dead coralline algae but I'm not 100% sure. Hopefully you'll get more responses.

 

[Tahoe61]

The second image is Peyssonnelia sp.

View Peyssonnelia sp.

 

[fagundespavinp3]

I love it! It's an awesome color