Spencer, Leonard James,  1870- <br/><br/>
A key to precious stones / 
by L. J. Spencer 
 - 3rd ed. 
 - London :  Blackle and s,  1952 
 - vi, 237 p. :  ill. ;  18 cm. 
<br/><br/> Includes index 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Precious stones
<br/><br/><label>Dewey Class. No.: </label>549