General Information
|
| Chemical
Formula: |
CaTiSiO5 = CaTiOSiO4 |
| Composition: |
Molecular Weight = 196.04 gm |
| |
Calcium 20.44 % Ca 28.61 % CaO |
| |
Titanium 24.42 % Ti 40.75 % TiO2 |
| |
Silicon 14.33 % Si 30.65 % SiO2 |
| |
Oxygen 40.81 % O |
| |
______ ______ |
| |
100.00 % 100.00 % = TOTAL OxIDE |
| Empirical
Formula: |
CaTiSiO5 |
| Environment: |
Magmatic, metamorphic and hydrothermal
rocks. |
| IMA
Status: |
Approved IMA 1960 |
| Locality: |
Laacher See and Eifel, Germany.
Madagascar |
| Name
Origin: |
Named after its chemical composition of
titanium. |
| Synonym: |
Sphene,
titanite |
| |
Titanite Image
|
| |
|
 
Click on the picture to go
to Sphene crystal.
|
|
| |
|
Crystallography
|
| Axial
Ratios: |
a:b:c =0.7522:1:0.8532 |
| Cell
Dimensions: |
a = 6.56, b = 8.72, c = 7.44, Z = 4;
beta = 119.716ø V = 369.62 Den(Calc)= 3.52 |
| Crystal
System: |
Monoclinic-Prismatic H-M Symbol (2/m)
Space Group: P21/a |
| x Ray
Diffraction: |
By Intensity(I/Io): 3.233(1)
2.595(0.9) 2.989(0.9) |
| |
|
| |
Physical Properties
|
| Cleavage: |
[110] Distinct, [100] Imperfect, [112]
Imperfect |
| Color: |
reddish brown, gray, yellow, green, or
red. |
| Density: |
3.4 - 3.56, Average = 3.48 |
| Diaphaniety: |
Transparent to translucent to opaque |
| Fracture: |
Sub Conchoidal - Fractures developed in
brittle materials characterized by semi-curving surfaces. |
| Habits: |
Massive - Lamellar - Distinctly
foliated fine-grained forms., Crystalline - Fine - Occurs as well-formed
fine sized crystals., |
| Hardness: |
5-5.5 - Apatite-Knife Blade |
| Luminescence: |
Non-fluorescent. |
| Luster: |
Adamantine - Resinous |
| Streak: |
reddish white |
| |
Optical Properties
|
| Optical
Data: |
Biaxial (+), a=1.84-1.95, b=1.87-2.034,
g=1.943-2.11, bire=0.1030-0.1600, 2V(Calc)=68-82, 2V(Meas)=20-56.
Dispersion r > v extreme. |
| Pleochroism
(x): |
colorless, greenish yellow, colorless,
or yellowish brown. |
| Pleochroism
(y): |
colorless, pink, greenish yellow,
yellowish brown, or yellowish green. |
| Pleochroism
(z): |
colorless, pink, reddish orange, pale
yellow, or grass green. |
| |
Classification
|
| Dana
Class: |
Nesosilicate Insular SiO4 Groups and O,
OH, F, and H2O |
| |
with cations in [6] and/or > [6]
coordination |
| |
Titanite group |
| |
- Titanite CaTiSiO5=CaTiOSiO4
P21/a
2/m
|
| |
Malayaite CaSnSiO5=CaSnOSiO4 A2/a 2/m |
| |
Vanadomalayaite
CaVOSiO4 C2/c 2/m |
| Strunz
Class: |
Silicates |
| |
Nesosubsilicates, with anions
unfamiliar to tetraheders, cationes with coordinationnumber between [8]
and [12] |
| |
STRUNZ - Silicates [Nesosubsilicates,
with anions unfamiliar to tetraheders, cationes with coordinationnumber
between [8] and [12 |
| |
- Titanite CaTiSiO5=CaTiOSiO4
P21/a
2/m
|
| |
Vanadomalayaite CaVOSiO4 C2/c 2/m |
| |
Malayaite CaSnSiO5=CaSnOSiO4 A2/a 2/m |
| |
- Trimounsite (Y) (Y,REE)2Ti2SiO9
P21/c
2/m
|
