Maybe you have a ring with a rare stone on your finger: grandidierite, hessonite, jeremejevite, dumortierite and taafeite are gems that are not easily found. Often these stones are used in jewelry, but they are not all the same and, above all, have a different value. Let’s see, therefore, the characteristics of these five stones: grandidierite, hessonite, jeremejevite, dumortierite and taafeite.
But with a premise: if you searched for one of these stones on Google, you will certainly have found dozens of sites that consider these minerals as if they had magical properties. Don’t believe a word in what they write. They are fake news, lies. The magical properties of minerals are only found in Harry Potter books or the like, do not think that a stone can cure or have even the slightest influence on your health or your psyche. Luckily. On the other hand, they are beautiful stones: isn’t that enough?
More generally, these five stones are part of the inanimate world: there are over 4,000 minerals on earth, many of which are very unlikely to see up close. And they often cost a lot, although not as much as the red diamond, which holds the price per carat record.
Grandidierite. It is a fairly rare green-blue, yellow-blue or blue-green color gem. Grandidierite was first discovered in Sri Lanka and is named after the French explorer and naturalist Alfred Grandidier (1836-1921). It was Grandidier who in 1902, in Madagascar, where most of these stones are mined today, was the first to publish the description. However, there are few grandidierite stones that can be cut and used for jewelry. According to Wikipedia, there are only two dozen stones of this type in the world that have been cut as precious gems. And, it seems, they are very expensive: more than $ 30,000 a carat. Grandidierite is also a fairly hard stone: 7.5 on the Mohs scale, like garnet.
Hessonite. It is a variety of garnet, also called cinnamon stone for its reddish yellow color. It is also found in Euroopa, in the Western Alps. Hessonite is a common variety of the grossular, a species of calcium aluminum that is part of the group of garnets. The name derives from ancient Greek: hesson means lower. But it does not refer to beauty, as to the fact that it is a type of garnet less hard than the others. Hessonite has, in fact, a hardness similar to that of quartz (about 7 on the mohs scale). This gemstone is found in Sri Lanka and India, Brazil and California.
Dumortierite. It is a mineral that takes its name from the French paleontologist Eugene Dumortier (1803-1873). The color ranges from blue to colorless, up to pale green, sometimes violet. It is considered to be a blue quartz, which ranges from around 7 to 8 on the Mohs scale. This stone can be completely opaque, or transparent, as if it were an ice blue crystal.
Jeremejevite. It is a mineral found for the first time in the Adun-Chilon mountains, in Siberia, in 1883. It has a hardness similar to quartz, from 6.5 to 7.5 on the Mohs scale, and is therefore usable for the creation of jewelry. The hue can range from blue to almost completely colorless. Jeremejevite is quite expensive: it is valued at around $ 2,000 per carat.
Taaffeite. It is one of the most expensive minerals used in jewelry: it is valued at 35,000 per carat. It is a very rare mineral and often mistaken for spinel. It was recently discovered in 1945. Dublin (Ireland), where it had already been cut and polished. But it was (incorrectly) labeled as spinel: only after a thorough gemological examination was it considered a different mineral. The main difference between spinel and taafeite, in fact, is the double refraction that this stone has. The gem is found in alluvial deposits within Sri Lanka and Tanzania.