Oriental Aquamarine — An Obsolete Trade Name for Blue-Green Sapphire
Oriental Aquamarine — An Obsolete Trade Name for Blue-Green Sapphire
A nineteenth-century misnomer for corundum, discouraged under modern disclosure
Oriental aquamarine is an obsolete trade term for blue-green or greenish-blue sapphire — corundum in the colour range that overlaps with aquamarine beryl. The term was used historically to suggest a connection to the more familiar gem species and to imply Asian provenance, but it does not describe a separate variety and is misleading on the species point. Modern disclosure standards, including the practice of the Gemological Institute of America and the American Gem Trade Association, identify the stone as sapphire, with a colour modifier where useful. The compound term oriental aquamarine should not be used in current trade practice.
Origin of the term
The use of oriental as a qualifier for varieties of sapphire is a nineteenth-century convention by which the trade communicated the colour of corundum to a market familiar with other species but not with the full colour range of sapphire. Oriental aquamarine sat alongside oriental emerald, oriental amethyst, and oriental topaz as colour-coded names for corundum in green, purple, and yellow, respectively. The vocabulary obscured the simpler fact that the stones in question were all sapphire.
Why the term is discouraged
The technical issue is that aquamarine is the blue to blue-green variety of beryl (Be3Al2Si6O18), a different species from corundum (Al2O3) with different hardness, refractive index, specific gravity, and optic character. Aquamarine has hardness 7.5 to 8 and refractive index near 1.564 to 1.595; sapphire has hardness 9 and refractive index 1.760 to 1.778. Calling a sapphire an aquamarine, even with the oriental qualifier, misrepresents the species and may mislead a consumer about the durability and value of the stone.
Modern laboratory practice identifies blue-green corundum as blue-green sapphire or green-blue sapphire, depending on which colour predominates. Disclosure of treatment, where applicable, follows the standard AGTA terminology. The term oriental aquamarine has no place in current laboratory or trade documents.
Practical guidance
A stone offered as oriental aquamarine should be examined for species. If it tests as corundum, it should be sold as blue-green sapphire with appropriate treatment disclosure. If it tests as beryl, the term aquamarine applies without the qualifier. The historical term may appear in older catalogues, antique-jewellery descriptions, and museum labels for nineteenth-century pieces; in such cases the species identification of the stone should be verified by gemmological examination, since older identifications were often inferential rather than analytical.
See also sapphire, oriental emerald, oriental amethyst, oriental topaz, aquamarine.