TY  - BOOK
AU  - Hurlbut , Cornelius S. 
AU  - Switzer, George S. 
TI  - Gemology
SN  - 0-471-42224-x
U1  - 553.8 
PY  - 1979///
CY  - New York
PB  - John Wiley
KW  - Gems
KW  - Precious stones
N1  - includes index
ER  -