Haüyn/hauynite

Haüyn is a rare mineral from the tectosilicate group, or a member of the sodalite group. It was first named as latialite in 1803 by Carlo Giuseppe Gismondi, according to the locality of the find, but without documentation. A few years later, it was renamed in honor of René Just Haüy, who is considered the father of crystallography. However, the name was not firmly established even after that, so in 1831 Louis Albert Necker de Saussiere decided to name this mineral berzelinite in honor of Jöns Jakob Berzelius. The final verdict on this mineral came only in 1868, when James Dwight Dana officially established the name hauynite, in Czech it is known as haüyn.

Its color is very deep blue, but it can also reach other shades. The scratch is white with a blue tinge, the luster is vitreous, some samples are fluorescent with a soft orange-violet color under short waves of UV light. It is both transparent and translucent. Hardness around 5.5-6 on the Mohs scale, making it suitable for collecting purposes, but less common in jewelery due to its more brittle nature. Haüyn is a very beautiful mineral that is popular both among collectors and among jewelers mainly because of its rarity, the prices of the most beautiful cut pieces can go up to the price of 3000 dollars per carat.