Barkan, Joanne. <br/><br/>
Hard as a rock /  [book] 

 - Englewood Cliffs, NJ :  Silver Press,  c1989. 
 - p. cm. 
 - First facts .
 - First facts (Englewood Cliffs, N.J.) .
<br/><br/> An introduction to rocks, their origins, and their evolution. 
<br/><br/><label>ISBN: </label>0671686569 (lib. bdg.) :  $8.98 0671686607 :  $4.95 
<br/><br/><label>LCCN: </label>89039192 /AC 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Rocks--Juvenile literature.<br/>Rocks.
<br/><br/><label>LC Class. No.: </label>QE432.2.  / .B37 1989 
<br/><br/><label>Dewey Class. No.: </label>552