Oxides and hydroxides: Perovskite
Diagnostic card.
Ca Ti O 3
Diamond orthogonality
Hardness 5,5
Specific weight 4
Cleavage is difficult to manifest
Fracture from semi-spherical to indeterminate
Color from yellow to black
Powder in color from yellow to light gray
Shine from diamond to semimetallic
Crystals, almost always well crystallized, have very clear pseudocubic symmetry. Most often presented in a simple form are clear cubes or octahedra, sometimes highly distorted. On the faces of the crystals, the hatching runs parallel to the ribs. A massive or granular shape is rare. It was named in honor of the Russian mineralogist Count LA Perovsky.
The shape of the crystals. Cubes, the faces of the cubes are excised by short strokes parallel to the ribs. Crystal structure. In the center of the cubic unit cell is the calcium ion, at the corners - titanium ions, and in the middle of each of the faces is the oxygen ion. Class of symmetry. Hexaoctahedral - m3m.
Diagnostic signs.
The mineral is heavy, hard, cleavage very imperfect along the planes of the cube. Fragile, with a semi-elongated or indefinite kink. Behavior in acids. It decomposes in boiling H2S04. The crystals are cubic, have shading, as in pyrite.
Origin.
It occurs as an accessory mineral in various intrusive and metamorphic rocks (serpentinites, chlorite and talc schists), in granatites and rodingites, in contact marbles. Among the varieties are discanital enriched with niobium, and knopite containing cerium.
Place of Birth.
In the form of ingrown or overgrown crystals found in chlorite schists (Tyrol), in some magmatic magnetite rocks (Finland, a rich deposit, suitable for development); Contact-metasomatic origin (Russia, Zlatoust region); In serpentine, in volcanic igneous rocks (in Vesuvius, Italy). Beautiful samples of this mineral are found in the Oka deposit in Quebec (Canada), where they are found in abundance. Occurs in the form of lamellar twins, sometimes in the form of parallel aggregates (Eifel mountains, Germany).
Perovskite is of exclusively collector value. Industrial applications find only varieties with a high content of niobium, cerium and other rare earth elements.
Perovskite in blue calcite. Akhmatovskaya spear, district of Zlatoust, Ural. 17x10x8 cm. The crystals are up to 3 cm. Photo: © А.А. Evseev.
- Ghetchellit - "New Almaden blend" - arsenide and antimony sulfide (modern sulfosol)
- Antimony is a toxic metal (semimetal) , widely used in metallurgy, medicine and engineering
- Zirconium - a rare and undiscovered metal and the most dangerous precious stone in oxide and salt
- Gold - yellow dangerous and poisonous metal of modern accurate digital and cable technologies
- Sulfur is a golden-yellow toxic substance and a sign of active volcanic activity
- Cadmium is an undisputed toxic silvery metal unknown to a wide range of people
- Lead - a toxic gray imitator of metallic silver and toxic metal blende
- Arsenic is a classic poison of medieval and modern poisoners and medicine in medicine
Poisonous and radioactive dangerous stones and minerals
** - poisonous stones and minerals (mandatory check in the chemical laboratory + explicit indication of toxicity)
** - radioactive stones and minerals (mandatory check on the standard dosimeter + ban on open sales in case of radioactivity exceeding 24 milli / g / h + additional measures of population protection)
Catalog of minerals and semi-precious stones of the world by groups
** - poisonous stones and minerals
** - radioactive stones and minerals
Comments
When commenting on, remember that the content and tone of your message can hurt the feelings of real people, show respect and tolerance to your interlocutors even if you do not share their opinion, your behavior in the conditions of freedom of expression and anonymity provided by the Internet, changes Not only virtual, but also the real world. All comments are hidden from the index, spam is controlled.