Fe-Ti oxides are an important source of titanium. The most common Fe-Ti oxides are ilmenite and rutile. Ilmenite forms from iron and titanium-rich liquids that separate from magma and sink to the floor, intruding into lower rock units like anorthosite. Ilmenite commonly forms solid solutions and is the most important ore of titanium. It often occurs in igneous and metamorphic rocks, as well as placer deposits, with large concentrations found in layered intrusions. Ilmenite forms late in magmatic differentiation from basic magma.
Fe-Ti Oxides: Introduction to Ilmenite Formation and Deposits
1. Fe –Ti oxides
Supervision by: Dr. Bottros R. Bakhit
Edited by: Mostafa Abdel Azim Masoud
image from RUSSIAN JOURNAL OF EARTH SCIENCES
VOL. 7, ES4001, doi:10.2205/2005ES000181, 2005
2. Introduction
Fe-Ti oxides are important source of
titanium.
Fe-Ti oxides include many minerals
but the most common are ilmenite
and rutile.
Titanum separated from magma and
sank to the magma floor due to its
high density and then form iron
titanium rich heavy liquids.
These liquids are then escaped
through fractures to intrude the lower
units which commonly are
anorthosite to form different Fe-Ti
oxide minerals.
Fe-Ti oxides often form solid
solutions .
4. Introduction to ilmenite
Formula: Fe2+TiO3
System: Trigonal
Colour: Iron black or black
Lustre: Metallic, Sub-Metallic
Hardness: 5 - 6
Member of: Ilmenite Group
Name: Named in 1827 by Adolph Theodor Kupffer after its type locality in
the Ilmen Mountains, Russia.
Magnetism: weakly magnetic (paramagnetic)
Geological Setting:Common accessory mineral in igneous rocks.
Also occurs in placer deposits.
Leucoxene - alteration product (which allows ilmenite to be distinguished from
magnetite and other iron-titanium oxides)
lmenite is the most important ore of titanium
Other Members of Group:
Ecandrewsite (Zn,Fe2+,Mn2+)TiO3
Geikielite MgTiO3
Pyrophanite Mn2+TiO3
5. Origin of Ilmenite
Ilmenite is considered as late maagmatic deposits.
Late magmatic deposits: are those deposits which crystallize close to the end of
magmatic differentiation
These deposits are produced from basic magma.
6. Origin of Ilmenite
a) Ilmenite is a common accessory mineral found in metamorphic and
igneous rocks. It is found in large concentrations in layered intrusions .
b) Magnesian (Mg) ilmenite is indicative of kimberlitic (ultramafic) and
forms part of association of minerals (mica-amphibole-rutile-ilmenite-
diopside) .
c) *Many mafic rocks ( such as gabbro, norite or anorthosite) contain
grains of intergrown magnetite and ilmenite, formed by the oxidation of
Ulvospinel.
d) Mangniferous ilmenite is found in granitic rocks (felsic) and granitic
pegmatite and also in carbonatite intrusions where it may also contain
anomalous niobium.
e) Ilmenite also occurs as discrete grains, typically with
some hematite in solid solution, and complete solid solution exists
between the two minerals at temperatures above about 950 °C.
f) Ilmenite is also found in placer deposits ( as black sands).
7. Distribution in the world
1)Russia : the Vishnevy-Il’men Mountains, Southern Ural Mountains.
2)Norway: the Lovozero massif, Kola Peninsula.
3) Switzerland: Binntal, Valais.
4)France: At St. Cristophe, Bourg d’Oisans.
5)USA, at Quincy, Norfolk.
6)Canada.
7)South Australia