How do I identify Changbaiite?

Changbaiite can be identified by its hardness of 5.5 on the Mohs scale. Look for these key characteristics when examining specimens.

How hard is Changbaiite?

Changbaiite has a hardness of 5.5 on the Mohs scale. This gives it moderate hardness.

Changbaiite

A variety of Minerals

What is Changbaiite?

Changbaiite (PbNb2O6) is a member of the oxide mineral class in which the mineral contains oxygen which is grouped along with one or two metal ion. Changbaiite is classified as a multiple Oxide XY2O6 and it generally has an ionic bond. Furthermore, it is also orthorhombic at a temperature of 25 °C and it changes to orthorhombic-tetragonal at 570 °C.

Changbaiite Market Value Calculator

Estimate the market value of Changbaiite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.

Changbaiite Localities Map

See where Changbaiite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.

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North ZoneCentral RidgeSouth Basin

Key Characteristics

Characteristics of Changbaiite

Changbaiite has a trigonal crystal system and a space group of R3m. Its lattice dimensions are a= 10.499 Å c = 11.553 Å. Changbaiite can be found as a small crystal with a tabular or spherules crystal shape. It can get up to 5mm in size and averages from 0.2 to 0.4 mm. Changbaiite's trigonal crystals show 3m symmetry and is bounded, in sequence of lessening prominence. Normally it is colorless or sometimes appears in different schemes of colors like cream white, pale brown, yellowish-brown, pale yellowish-green with white streaks and adamantine to pearly luster. Changbaiite is nonmagnetic and breakable. Also, it possesses dual quality of translucent to transparent. It has perfect basal cleavage and distinct rhombohedral cleavage with hackly fracture, on the other side spherulitic grains are conchoidal. Ultraviolet light and cathode rays have no fluorescent effect on changbaiite and this is not soluble in hydrochloric acid, nitric acid or sulphuric acid but conditionally less soluble in hot phosphoric acid. Changbaiite has a hardness of 472.4 kg/mm on the Vickers hardness scale and 5.3 on mohs scale. In an optical spectrum changbaiite is uniaxial positive and it can be biaxial. Changbaiite reflectance, which is the fraction of incident radiation reflected by a surface, is 15.86 at 546 nm.

Composition of Changbaiite

The chemical formula of changbaiite is PbNb2O6 after microprobe analysis of kaolinite-filled veins. It is composed of iron (II) oxide FeO 0.94%, lead oxide PbO 41.51%, iron (III) oxide Fe2O3 0.42%, titanium dioxide TiO2 0.95%, niobium pentoxide Nb2O5 55.62%, and tantalum pentoxide Ta2O5 0.98%, which produce the chemical formula (Pb0.95Fe2+0.05)(Nb1.95Ti0.05Fe3+0.02Ta0.01) or PbNb2O6. It was also examined by the spectrographic method which represents Sb 0.3, Si 0.1, Ba 0.2, Ca 0.1, and minor traces of copper, magnesium and aluminum. Subbarao suggested that Changbaiite formula PbNb2O6 can vary. He represented lead niobate by A1+xNb2O6 where the A site is an ion (usually lead) and he found that the upper limit of x in his representation was about 0.15 and a low limit between −0.07 and −0.08. In conclusion, the formula ranges from Pb0.92Nb2O6 to Pb1.15Nb2O6.