New/old Rocks?

[hahicx]

What do people/autominers mean when they say New or Old Rocks?

Thanks.

[Naum]

Here:

Tell the difference

http://i32.tinypic.com/e6u7ma.jpg

[hahicx]

So it depends whether the whole rock is the colour, or just a crack.

So old is whole thing, new is just a crack? Is that right?

Thanks.

[Cerium]

Correct.