This name, meaning “gift of the sun," has been coined fairly recently for the yellow-green variety of beryl.
Appearance Its main characteristic is its color, which ll the yellow-green of olive oil. The shade, however, may very considerably, and it is hard to establish a dividing line between heliodor and golden beryl. The normally medium or largish stones are generally given an oval or, more rarely, I step cut. They may have the liquid inclusions typical of beryl, but are usually quite clear.
Distinctive features Yellower versions can look very much like olivine. But the strong birefringence of the latter, visible merely by observing the facet edges with a len. readily distinguishes it. Heliodor may also be very similar to chrysoberyl; the latter, however, is usually more Iustroul, and, of course, has different physical characteristics. Finally, heliodor can bear a resemblance to some yellow-green tourmalines, though the color of these is slightly duller. Here, too, the surest way to establish a distinction by measuring the physical characteristics. '
Occurrence The best specimens come from Namibia, but heliodor is also found in Madagascar and Brazil.
Value Collectors value heliodor at least as highly as aquamarine. It is not common on the market.
Simulants and synthetics A yellow-green variety of synthetic spinel is used to imitate heliodor. Synthetic heliodor. however, does not exist.