Titanite

Crystal system · Monoclinic
Titanite specimen
Photo: Fred Kruijen · CC BY-SA 3.0 nl via Wikimedia Commons

About Titaniteextended article

Elemental Composition (by mass)
ElementMass %Visual
O Oxygen40.81%
Ti Titanium24.42%
Ca Calcium20.45%
Si Silicon14.33%
Computed from simplified end-member formula. Solid-solution series, water content, and trace substitutions cause real-world variation.
IMA Abbreviation (Whitney-Evans 2010)
Ttn
→ Titanite
Same as sphene
Standard symbol from American Mineralogist (Whitney & Evans, 2010). Used in thin-section labeling, phase diagrams, and IMA-style species records.
Pronunciation
/ˈtaɪtənaɪt/
TIE-tuh-nite
from titanium
Lapidary & Faceting Recommendations
Recommended cut:
oval / round brilliant
Also seen:
cushion, pear
Typical yield:
25% of rough
Same as sphene — synonym.
Luster
adamantine
High RI + high dispersion — strong fire on faceted material.
Diaphaneity (Transparency)
transparent
Same as sphene.
Type Locality
Passau — Germany
Described 1795 by Klaproth
Specific Gravity
3.45–3.55
g/cm³
medium
Same as sphene.
For comparison: water = 1.00, glass ≈ 2.5, quartz = 2.65, corundum ≈ 4.00, galena ≈ 7.50, gold ≈ 19.3.
Twinning Laws
Contact twin {100}contact
Wedge-shaped flattened twins common from Alpine clefts.
Pleochroism (trichroic)
Axis a
pale yellow
Axis b
reddish yellow
Axis c
green-yellow
Strength: strong
Same as sphene — synonym.
Mohs 5–5.5
Vickers (~) 540 HV
Knoop (~) 620 HK
Geological setting
Metamorphic
Element composition by mass

Formula: CaTiSiO₅ · molar mass: 196.03 g/mol

O 40.81%
Ti 24.42%
Ca 20.45%
Si 14.33%

Computed from atomic weights (IUPAC 2021). Site-occupancy groups (Fe,Mn) split equally.

Optical Effects
diamond, demantoid)">High dispersion
Mohs Hardness 5–5.5
1
Talc
2
Gypsum
3
Calcite
4
Fluorite
5
Apatite
6
Orthoclase
7
Quartz
8
Topaz
9
Corundum
10
Diamond

Titanite (Sphene) sits at 5–5.5 on the Mohs scale — can be scratched by a steel knife.

Colors:
Streak
White
Crystal system
Monoclinic
SilicatesSilicates (Nesosilicates)
TL;DR · 1 min read
Titanite (CaTiSiO₅), historically called "sphene" for its wedge-shaped crystals, is a calcium-titanium silicate famous for adamantine luster, strong dispersion (higher than diamond! ), and emerald-green to honey-yellow gem material.

Titanite (CaTiSiO₅), historically called “sphene” for its wedge-shaped crystals, is a calcium-titanium silicate famous for adamantine luster, strong dispersion (higher than diamond!), and emerald-green to honey-yellow gem material. Pakistan (Skardu) and Brazil yield gem-quality crystals; metamorphic occurrences supply the larger collector specimens.

More minerals to explore

Frequently asked questions

What is the chemical formula of Titanite?

The chemical formula of Titanite is CaTiSiO5.

What crystal system does Titanite belong to?

Titanite crystallises in the Monoclinic crystal system.

References & databases

Mindat.org is the world’s largest open mineralogy database. Our descriptions are written independently and fact-checked.