TY  - BOOK
AU  - Kraus,E.H.
AU  - Slawson,C.B.
TI  - Gems and gem materials
U1  - 549 
PY  - 1953///
CY  - N.Y.
PB  - McGraw-Hill
KW  - Chemistry and Allied Sci
KW  - Chemistry and Allied Science
ER  -