black tourmaline stone(semi-precious stone)
The shape is good, high quality, worth having
Natural Stones, non synthetic
Typical chemical analysis:
element | Percent by weight (%) |
SiO2 | 37.05 |
Al2O3 | 29.8 |
MgO | 8.05 |
CaO | 1.18 |
K2O | 0.09 |
FeO | 8.33 |
NaO2 | 1.19 |
Cr2O3 | 0.22 |
B2O3 | 10.16 |
TiO2 | 0.44 |
Typical chemical formula:
(Ca,K,Na,[])(Al,Fe,Li,Mg,Mn)3(Al,Cr, Fe,V)6(BO3)3(Si,Al,B)6O18(OH,F)4
Typical physical properties:
Density | 2.82-3.32 |
Hardness | 7-7.5 |
Crystal habit | Parallel and elongated. Acicular prisms, sometimes radiating. Massive. Scattered grains (in granite) |
Crystal system | Trigonal |
Cleavage | Indistinct |
Fracture | Uneven, small conchoidal, brittle |
Luster | Vitreous, sometimes resinous |
Streak | White |
Specific gravity | 3.06 (+.20 -.06) |
Polish luster | Vitreous |
Optical properties | Double refractive, uniaxial negative |
Refractive index | nω=1.635–1.675, nε=1.610–1.650 |
Birefringence | -0.018 to -0.040; typically about .020 but in dark stones it may reach .040 |
Pleochroism | typically moderate to strong Red Tourmaline: Definite; dark red,light red |
Dispersion | .017 |
Ultraviolet | pink stones—inert to very weak |
Fluorescence | red to violet in long and short wave |
Absorption spectra | a strong narrow band at 498 nm, and almost complete absorption of red down to 640nm in blue and green stones; red and pink stones show lines at 458 and 451nm as well as a broad band in the green spectrum |
Applications:
1. High pure tourmaline is the bijou that can be made into jewelry such as necklace bracelet and so on. |
2. It can be used in deodorizing wall paper, floorboard, ceiling board furniture inner wall coasting material and concrete. |
3. Packing material with the function of antibacterial and fresh keeping. |
4. The healthy filling of cigarette filter tip. |
5. Purification materials for water and air. |
6. Additive of toothpaste and cosmetic |
7. Antibacterial coating and is use in electronic equipment and house hold electric. |
8. Made composite ceramic with the function of antibacterial sterilization and deodorization. |
Tourmaline have the special properties of piezoelectricity and pyroelectricity so it have the electromagnetic radiation of far-infrared region producing negative oxygen ion to antibacterial and deodorize.
high pure tourmaline can be made into jewelry such as necklace bracelet and so on.
If need, please contact me. Tel:86-0311-86040958-804 mobile NO.:15833996471