Ravid, U., Department of Medicinal, Spice and Aromatic Plants, Agricultural Research Organization, Newe Ya'ar, Post, Haifa, 31-999, Israel
Bassat, M., Department of Medicinal, Spice and Aromatic Plants, Agricultural Research Organization, Newe Ya'ar, Post, Haifa, 31-999, Israel
Putievsky, E., Department of Medicinal, Spice and Aromatic Plants, Agricultural Research Organization, Newe Ya'ar, Post, Haifa, 31-999, Israel
Ikan, R., Department of Organic Chemistry, Natural Products Laboratory, Hebrew University of Jerusalem, Jerusalem, 91-904, Israel
Weinstein, V., Department of Organic Chemistry, Natural Products Laboratory, Hebrew University of Jerusalem, Jerusalem, 91-904, Israel

1H‐NMR examination of (+)‐terpinen‐4‐ol, performed in the presence of various molar ratios of a chiral lanthanide shift reagent Eu(hfc)3, showed that the enantiomeric composition of (+)‐terpinen‐4‐ol isolated from the essential oil of sweet marjoram is 73%(+): 27%(−). Peak assignment of the enantiomers was achieved by spiking the natural (+)‐enantiomer with the commercial (−)‐alcohol. The method will readily reveal adulteration of natural oils with racemic synthetics. Copyright © 1987 John Wiley & Sons, Ltd