TY  - BOOK
AU  - Dietrich,R.V.
AU  - Skinner,Brian J.
TI  - Gems, granites and gravels: knowing and using rocks and minerals 
SN  - 0521344441 :
U1  - 549 
PY  - 1990///
CY  - Cambridge
PB  - The University Press
KW  - Mineralogy
KW  - Petrology
N1  - Includes index
ER  -