Hi Tony,
Rocks are not "alive" because they have no Bio-Machinery and DNA programming. No moving parts to speak of.
OK. Did anyone say they were alive?
Now one could mould sand, etc. and cook it to create a hard rock that is "designed".
Agreed. Artificial rock is commonplace.
If you rough it up some what you may not be able to "see" the difference from one naturally created verses the masterfully designed rock that "looks" natural.
Sure, a rock could be made that would be realistic enough to fool me, but then, I'm not a geologist, just an amateur rock collector. Even so, I can recognise most of the man-made rock-like substances that one might find.
Let's say that I am fooled though; what does this prove, except that my knowledge of rocks and rock-like objects is flawed? Who does the rock have to fool before we declare it to be indistinguishable from a natural rock? Me? You? A six week old baby? A professor of Geology?
How does any of this get us any closer to finding out whether the rock is designed or not?
"The Bible is like a person, and if you torture it long enough, you can get it to say almost anything you'd like it to say." -- Rev. Dr. Francis H. Wade