Thomas chinnappan geologist keeranur, pudukkottai, tamilnadu, india.

1. Thomas chinnappan
geologist
keeranur, pudukkottai, tamilnadu, india.

2. Definition : Textures defined as the spatial relations
within and among minerals and fluids , regardless of
Scale (or) Origin.
A Common definition for ore textures refers to
volume , grain size, shape, spatial distribution
association of each mineral in the ore.
ORE TEXTURE

3. optical image analysis for
textural ore

4. Optical mineralogy
 Texture Natural arrangements of minerals
 It is useful for determining the rock type.
 The Crystallization sequence
 Constraining pressure _temperature history
 Noting weathering and their alteration

5. Isotropic Materials
 Isometric refers to the optical properties of
the mineral , which are the same and their
independent of the orientation.
Example : Isotropic minerals
• Isotropic materials show the same properties
in all directions.

6. Anisotropic Materials
 Anisotropic behavior when changing orientation
include different absorption of light, different
refractive indexes etc…
• All minerals , other than those belonging to
the isometric system , are anisotropic.
• Properties of material identical for depend
on the direction.

7. Optical microscopy
 Light passes through thin sections _ rock cut
and polished to about 0.3 mm thickness.
 Use properties of light absorption and their
propagation through a mineral _ affected by
atomic arrangement and composition.
 The properties of light associated with an
techniques governing the use of a petrographic
microscope..

8. Microscopic ore of olitic hematite
and iron ore pellets

9. Magmatic ores
Cumulus Texture :
 Settling of an ore deposit from a crystalizing magma
Example : Chromite
Intergranular (or) intercumulus Texture :
• Ore mineral occurs as an intergranular anhedral
phase relative to the other gangue mineral
• This ore mineral crystallizes Late in the magmatic
sequence , ( relative to the other gangue minerals )

10. Magmatic ores
Exsolution Texture :
• Exsolution textures usually indicate
a slow (or) intermediate cooling rate
• Exsolution textures as difficult to tell
apart from, some textures that from by replacement.

11. THANK YOU