What kind of rock do I have?

[mmync]

O am not sure if I should use these 2 pieces of rock, they where like the first 2 pieces that I bought. For starters they are pretty much yellowish/orange in color. They kinda look like big pieces of lava rock that you use outside for landscaping but they are not red and they are alot bigger like i said, about 6" wide 9" tall. They both have 2 really nice holes in them. I know they havent been cured yet, which isn't a problem. My only concern is that they are super clean, which makes them look totally artificial looking and they dont match all my other already cured rock. So do you guys think I should use them and that eventually they will look like my cured rock, kinda green and redish?

 

[buzz]

Have they been in a saltwater tank before? If so, did you ever notice anything detrimental about them there? I can't tell you what the rock is actually composed of (minerals, etc.), but if it has worked before, it may work again. I would only be concerned with any possible copper present in it, but if that is not a concern, it may work fine.