Chemical Formula : Fe3O4
• Class : Oxides and Hydroxide
• Group : Spinal
• Uses : Major ore of iron and as
mineral
• Composition : Molecular weight 231.54 gm
Iron 72.36 % Fe
31.03 % Feo
68.07 % Fe2O3
Oxygen : 27.64 %
• Empirical
formula : Fe3+2Fe3+O4
• Environment : Common accessory mineral in
igneous and metamorphic
rocks.
• Locality : Many localities and
Environments world wide.
• Name of origin : Named for Magnes, a Greek
shepherd, who discovered the mineral on mountain Ida. He
noted that the nails of his shoe and Iron ferrule of his
staff
clung to a rock
• Synonym : Lodestone
Magnetic iron ore.
PHYSICAL PROPERTIES OF MAGNETITE
• Colour : Grayish black, Iron black
• Cleavage : None
• Luster : Metallic to dull.
• Diaphaneity : Opaque
• Streak : Black
• Luminescence : None
• Hardness : 5.5 – 6.5 knife Blade-
Orthoclase
• Specific
gravity : 5.17 – 5.18
• Transparency : Crystal are opaque
• Crystal System : Is isometric, 4/m bare 32/m
• Crystal habits are
typically octahedrons but rarely
rhomododeccehedron and other isometric forms, most
commonly found massive or granular. Twinning of
octahedrons into spinal law trains is seen occasionally.
• Cleavage is absent
although octahedral parting can be seen
on some specimens.
• Fracture is
conchoidal
• Associated minerals
are talc and chlorite pyrite and
hematite.
• Other
characteristics: Magnetism stronger
is massive
example than in crystals, striations on crystal faces.
• Best field Indicator
is magnetism, crystal habit and streak.
Iron oxides:
1. Iron II oxide (Feo) (Ferrous oxide)
2. Iron III oxide (or) ferric oxide Fe2O3 (Hematite) Red iron
oxide
3. Iron II, III oxide (or) ferrous ferric oxide (Fe3O4) Magnetite –
Black coloured Magnetite
4. FeO (OH) Yellow iron oxide
5. (Fe2O3.H2O) hydrated iron oxide yellow iron oxide
Magnetite is another form of biological iron derived
apparently from the iron in ferritin.
Heating the hydrous oxide to 2000C, gives red brown
Fe2O3. The structure comprised a hexagonally close packed
lattice of O2- ions with Fe3+ ions
in the two thirds of the
octahedral holds. However, if Fe2O4 is oxidized Fe2O3 is formed
which has a cubic close packed arrangement of 2- ions randomly
distributed in both the octahedral and tetrahedral sites.
Fe3O4 is formed as a black
solid by igniting Fe2O3 at
14000C, Fe3O4 is mixed oxide. FeII Fe2IIIO4 and has an inverse
spinal structure. The O2- ions are cubic close packed
with the
larger Fe2+ in one quarter of the octahedral holes. Fe2O3, Fe3O4
all tend to be nonstorchiometic.
The oxide Fe3O4 occurs as the mineral magnetite. It is a
FeII FeIII mixed oxide with inverse spinal structure with FeII in
octahedral interstices and FeIII ions half in tetrahedral and half
in octahedral interstices of a cubic close-packed array
of oxide
irons. The electrical conductivity is probably due to
rapid valence
oscillation between the Fe stir. It can be made by
oxidation of
Fe2+ with alkaline KNO3 in the presence of phosphate or by
reaction of acidified jocosities.
Magnetic materials are classified as
1. Dia magnetism
2. Para magnetism according to their properties in a
magnetic field.
Diamagnetism is based on orbital motion of the
electrons and is induced by the applied magnetic field.
Paramagnetic substances are characterized by one or more
unpaired electrons, magnetization is aligned parallel to
the
external field.
In solid bodies, strong interaction may develop between
adjacent ions. So that spontaneous magnetization results.
Pure
magnetic iron oxide particles used as diagnostic agent in
nuclear
MRI.
Magnetic Therapy is complementary or an alternative way
to enhance the relief of discomfort and the body’s natural
healing
process. According to human physiology, the first thing
to know
is that the human body is an electromagnetic organism.
Electricity flows through the nerves in our body as the
same way
electricity flow through an electrical wire. All cells
have two
magnetic poles, north and south, in their DNA.
Magnetic therapy today
Today in Japan and other Asian countries, therapeutic
magnets are licensed as medical devices, Contemporary
western
medicine uses forms of magnetic energy for diagnosis, for
example in magnetic resonance imaging (MRI), and as an
aid to
accelerate the healing process, following breaks and
fractures in
bone structure. Magnetic therapy is now gaining
widespread
acceptance from the US medical community (recent
testimonials)
and it is becoming increasingly popular among osteopaths,
physiotherapists and chiropractors as a means of treating
a wide
range of health problems, including chronic back
discomfort,
arthritis, and sporting injuries.
Scientists have studies magnet
therapy for the following
health problems
Fracture healing
Osteoarthritis
Many types of pain
Ankle pain
Knee pain
Back pain
Iron Salts:
Action: Irritant
Signs and symptoms
Gastritis
Haemetemisis
Encephalopathy
Diarrhoea
Fatal dose : Uncertain
Fatal Period: Uncertain
Treatments
Gastric Lavage
Leave dilute NaHCo3 in stomach
Electrolyte correction
Desferrioxamine
Medico legal point and poison
sources: Accidental through
over dosage.
