De Silva, R.N.P. <br/><br/>
Gemmology : A practical approach 

 - Rathmalana  Vishva leka   2002 
 - 165p.,2pl., ill.,  22 cm 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Gem <br/>Gemmology
<br/><br/><label>Universal Decimal Class. No.: </label>549.091  / DES