Petersen, Christine <br/><br/>
Groovy gems / 
Christine Petersen. 
 - 32 pages :  illustrations (chiefly color), map;  21 cm. 
 - Checkerboard Science Library. Rock on! A look at geology .
<br/><br/> Includes index. 
<br/><br/>Erasmus's lucky pebble -- What is a gem? -- Most gems are minerals -- Six crystal systems -- Magma gems -- Water gems -- Living gems -- Imitations and synthetics  -- Cultured pearls -- Working with gems -- Then and now. 
<br/><br/><label>ISBN: </label>9781604537437 (alk. paper) 
<br/><br/><label>LCCN: </label>2009027728 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Gems--Juvenile literature.<br/>Precious stones--Juvenile literature.
<br/><br/><label>LC Class. No.: </label>QE392.2  / .P48 2010 
<br/><br/><label>Dewey Class. No.: </label>553.8