Morganite belongs to the same gemstone family as emerald, aquamarine, golden beryl and bixbite. Among these beryls, morganite and the raspberry-red bixbite are the rarest. In fact bixbite is only found in the state of Utah in the USA. Morganite is not quite as scarce, but still counts as a rare variety.
There has been some attempt in the jewelry trade to change the name of morganite to "pink emerald." But this should be seen as just a marketing ploy to bring pink beryl to the attention of the public. The official mineral name for pink beryl continues to be morganite.
Like the other members of the beryl family, morganite is aluminum beryllium silicate. The source of the pink colouration is not well understood. Some scientists attribute morganite's colour to traces of manganese, while other sources attribute the colour to the element caesium. Morganite's colour can vary from soft pink to violet, salmon and peach.
In common with other beryls, morganite has very good hardness, with a rating of 7.5 to 8 on the Mohs scale. The refractive index is 1.562 to 1.602. Beryl generally has a density or specific gravity of 2.66 to 2.87, but morganite is slightly denser than other beryls, at 2.71 to 2.90. Unlike emerald, which tends to have significant inclusions, morganite is usually quite clean.
Morganite is routinely heat treated to improve its delicate colour and remove any yellow tones. Heating is done at relatively low temperatures (about 400 degrees centigrade) to achieve this effect.
Morganite deposits are found in Afghanistan, Brazil, China, Madagascar, Mozambique, Namibia, Zimbabwe and the USA (California and Maine).