Self-similar bismuth is a mineral from the class of native elements . Easily soluble in nitric acid , melts at 271.3 ° C. It has strong diamagnetic properties.
| Bismuth Native | |
|---|---|
 | |
| Formula | Bi |
| Impurity | Fe , As , S , Sb , Te |
| Physical properties | |
| Colour | Reddish white, turning creamy white; from the surface rainbow pinkish, yellowish, bluish |
| Shine | Metal |
| Transparency | Opaque |
| Hardness | 2–2.5 |
| Cleavage | Perfect in {0001} and {1011}, very imperfect in {1014} |
| Kink | Uneven |
| Density | 9.7-9.83 g / cm³ |
| Syngonia | Trigonal |
Content
Crystallography
| Point group | 3m (3 2 / m) - Hexagonal Scalenohedral |
|---|---|
| Space group | R3m (R3 2 / m) |
| Syngonia | Trigonal |
| Cell options | a = 4.55 Å, c = 11.85 Å |
| Attitude | a : c = 1: 2.604 |
| Number of formula units (Z) | 6 |
| Unit cell volume | V 212.46 ų (calculated according to the unit cell parameters) |
| Twin | Usually polysynthetic twinning |
Optical Properties
| Type of | anisotropic |
|---|---|
| Optical anisotropy | distinguishable |
| Color in reflected light | brilliant creamy white, turning into yellow |
| Pleochroism | weak |
Selection Forms
Native bismuth is characterized by granular aggregates, individual grains, skeletal crystals and dendritic excretion. Pseudocubic crystals are very rare.
Natural and Synthetic
Native bismuth is formed in hydrothermal veins, where it is associated with other minerals of bismuth, antimony , arsenic , gold and silver .
Artificial bismuth is also synthesized. In skeletal synthetic crystals, ribs are well developed. Artificial bismuth forms pseudocubic forms with stepped voids instead of faces.
Application
Bismuth is used in the production of fusible alloys with tin , indium , lead , zinc and other metals. It is also used in welding pastes for special works, pharmaceuticals (drugs for stomach ulcers and cancer), the cosmetics industry (pastes for the manufacture of lipsticks), and the manufacture of superconductors and batteries.
Deposits
Native bismuth is relatively rare. The main deposits of this mineral are in Australia , Russia , Kazakhstan , Spain ( Los Pedroches , Cordoba ). Also found in Bolivia , the UK , Germany and the USA .
Literature
- Dymkov Yu. M. Skeletal forms and dendritic textures // In the book: Paragenesis of minerals of uraniferous veins. M., "Nedra", 1985, pp. 62–70.
- Malinko S.V., Dubinchuk V.T., Nosenko N.A. Native bismuth in datolithic ores of the Dalnegorsky boron deposit // Mineral. J., 1990, 14, No. 1, p. 42-52 (abstract - RZH "Geology", 1992, 6B213)
- Palache C., Berman H., Frondel C. (1944), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana Yale University 1837-1892, Volume I: Elements, Sulfides, Sulfosalts, Oxides. John Wiley and Sons, Inc., New York. 7th edition, revised and enlarged, 834pp .: 134-135.