Sulphides: Geocronite

Diagnostic card.

Pb ₅ As Sb S ₈
Singonia monoclinic
Hardness 2-3
Specific weight 6,4
Color lead-gray
Glitter metal

The mineral is usually dense or granular. His crystals, in appearance pseudohexagonal, are always a rarity. Here you can find quite large crystals (up to 15x15x10 cm), similar to those exhibited in the window of the Museum of the University of Pisa. The vast majority of geocronites are characterized by a high content of silver.

In polyr., Sl. In reflection. St. White with a weak greenish tinge, which is clearly visible only when the geocronite is in association with galena and other white minerals. Otrazh.posp. (In%): for green rays 37, for orange - 30.5, for red - 29.5; By measurements with a photocell - 40.9. Doubling is weak: the color varies from light gray to dark gray, bluish-gray or from yellowish white to greenish white; In the immersion, the color effect is enhanced. Clearly anisotropic. Internal reflexes are not observed. Characterized by polysynthetic twins. It is polished well.

The structure is not installed. Presumably not all lattice sites are filled, as indicated by the discrepancy between the dimensions of the lattice, the composition computed and the measured ud. Weights. The crystals are tabular in (010), pseudohexagonal development, only slightly elongated along the c axis. The crystals are tabular in (010), pseudohexagonal development, only slightly elongated along the c axis. Two. Very common, often repeated: by (001), possibly also by (101).

Origin.
It is often found in the form of rounded concretions in galena.

Place of Birth.
Geocronitum in several Swedish fields, in Kilbriken (Ireland), in Maredo in the Asturias region (Spain), in the Tintic region of Utah, as well as in the states of Virginia, California and Idaho (USA). In Italy, magnificent crystals were mined in the Canal del Angina in Val di Castello, near Pietrasanta (Lucca province). Small crystals of a perfect geocronite are often found in marbles of Carrara, accompanied by pyrite, sphalerite, colusite, burnonite, enargite, sulvanite, etc.

ADR 1
The bomb that explodes
They can be characterized by a number of properties and effects, such as: critical mass; Scatter of fragments; Intensive fire / heat flow; bright flash; Loud noise or smoke.
Sensitivity to shocks and / or impacts and / or heat
Use the shelter, while keeping a safe distance from windows
Orange sign, the image of a bomb in the explosion

ADR 6.1
Toxic substances (poison)
Risk of poisoning by inhalation, in contact with skin or if swallowed. Dangerous to aquatic environment or sewer system
Use a mask for emergency leaving the vehicle
White diamond, ADR number, black skull and crossbones

ADR 5.1
Substances that are oxidized
Risk of violent reaction, ignition or explosion if exposed to flammable or flammable substances
Do not allow the formation of a mixture of cargo with flammable or combustible substances (eg sawdust)
Yellow diamond, ADR number, black flame above the circle

ADR 4.1
Highly flammable solids , self-reactive substances and solid desensitized explosives
Risk of fire. Flammable or combustible substances can ignite from sparks or flames. May contain self-reactive substances capable of exothermic decomposition in the case of heating, contact with other substances (such as: acids, heavy metal compounds or amines), friction or impact.
This can lead to the emission of harmful or flammable gases or vapor or spontaneous combustion. Containers can explode when heated (over-dangerous - practically do not burn).
Risk of explosion of desensitized explosives after loss of desensitizer
Seven vertical red stripes on a white background, equal in number, ADR number, black flame

ADR 8
Corrosive (corrosive) substances
Risk of burns from skin corrosion. They can react violently with each other (components), with water and other substances. The substance that spilled / crumbled can emit a corrosive vapor.
Dangerous to aquatic environment or sewer system
White upper half of diamond, black - lower, equal, ADR number, test tubes, hands

• 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 poisonous 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