Pearl, Richard M.  1913-1980. <br/><br/>
Colorado gem trails and mineral guide / 
Sketch maps by Mignon W. Pearl and Eva C. Keller. 
 - 176 pages  illustrations 
<br/><br/> Includes bibliography. 
<br/><br/><label>LCCN: </label>58001938 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mineralogy--Colorado.<br/>Gems--Colorado.