On completion of this module, students should be able to:
1) use a petrological microscope and a virtual, online microscope to perform optical tests, describe and identify minerals and interpret textures;
2) demonstrate in writing a knowledge of mineralogy and mineral chemistry and how they relate to each other, the formation of economic mineral deposits and Earth's overall composition.

ONLINE LECTURES:

Lecture 1: Minerals, crystals and polarised light.
Course outline; the nature of ordinary and plane polarized light; optical properties under the petrological microscope in plane polarized light and between crossed polars; crystalline structure, symmetry and the seven crystal systems. Use of the Michel - Levy chart.

Lecture 2: Silicate minerals.
Silicate composition of crust and mantle; The SiO4 tetrahedron, silicate polymerization and silicate classification, with examples of each class; Goldschmidt's rules, chemical substitution and solid solution; examples of silicate solid solutions; relationships between silicate properties and silicate classification.

Lecture 3: Mineral stability and phase diagrams.
Controls on mineral stability and its depiction on phase diagrams; crystal-liquid binary diagrams (anorthite-diopside and plagioclase); eutectic points; the Lever Rule in binary diagrams; polymorphism, the SiO2 phase diagram and the geological occurrence of SiO2 polymorphs; alkali feldspar solvus diagram and perthite textures.

Lecture 4: Mineral – melt partitioning of elements.
Olivine – basalt liquid element partitioning; definition of partition coefficient and bulk partition coefficient; major and trace elements; compatible and incompatible elements; controls on element partitioning; trace element substitution; behaviour of the rare earth elements; partitioning during batch melting and fractional crystallization; economic importance of extreme fractional crystallization.

Lecture 5: Sandstones and carbonate sedimentary rocks.
Outline of the mineralogy and texture of sandstones: detrital grains, detrital matrix, diagenetic overgrowths and cements; mineralogy; size, rounding and sorting of detrital grains; porosity and permeability. Outline of the mineralogy and texture of limestones and dolomites: bioclasts, limestone mud and detrital minerals; primary and secondary dolomites.

Lecture 6: Igneous textures.
Crystallization from magmas, volcanic and plutonic, and sequence of crystal growth, with implications for mineralogy and texture of igneous rocks. Sequence of crystal growth (e.g. anorthite-diopside phase diagram)

Lecture 7: Metamorphic textures.
Solid state recrystallization in different temperature and confining pressure environments and implication for the mineralogy and textures of metamorphic rocks.

Lecture 8: Hydrothermal minerals and ore deposits.
Hydrothermal fluids; concentration of metals and non-metals in fluids; crystallization from fluids; sulphides, sulphates, halides, carbonates and native metals; common types of hydrothermal ore deposit.

Lecture 9: Magmatic ore deposit and their minerals.
Magmatic ore deposits - layered and other mafic intrusions, komatiites and pegmatites; how rare elements are concentrated in some magmas.

Lecture 10: Chemical composition of the Earth.
Methods for estimating average chemical composition of the upper and lower crust; mantle xenoliths and ophiolites as samples of the mantle; geophysical constraints; meteorite evidence for composition of the core and mantle; evidence from chondritic meteorites for bulk earth composition; chondrite normalisation.

ONLINE EXERCISES AND PRACTICAL PREPARATION:

Week 1: Practical preparation: mineral hand specimen description and use of the petrological microscope.
An introduction to simple properties that can be used to describe and identify hand specimens of minerals: colour, transparency, streak, lustre, hardness, cleavage and fracture, specific gravity, crystal habit, magnetism, reaction with HCl. The petrological microscope: its parts and their functions.

Week 2: Exercise: the Periodic Table – elements, ions, bonding and chemical compounds.
Information and self-assessment related to the Periodic Table – elements, chemical symbols, atoms, ions, ionic charge and radius, co-ordination numbers, chemical bonds and chemical formulae.

Week 3: Exercise: silicate minerals – atomic structure and chemical composition.
Information and self-assessment on: silicate polymerization and atomic structures; classification of silicate minerals; the behaviour of aluminium in silicate minerals; element substitution, solid solution chemistry and its graphical representation; optical determination of plagioclase composition.

Week 4: Exercise: mineral stability and phase diagrams.
Information and self-assessment on: plotting, calculations and interpretations related to phase diagrams, including binary crystal-liquid (anorthite-diopside, plagioclase), solvus (alkali feldspar) and polymorphic pressure - temperature (SiO2, Al2SiO5) examples.

Week 5: Exercise: mineral – melt partitioning.
Information and self-assessment on: interpretation of plagioclase phenocryst zoning and reverse zoning; interpretation of major and trace zoning in phenocryst olivine; effects of extreme fractional crystallisation on incompatible element concentrations.

Week 7: Practical preparation: Alteration reactions between minerals and fluids
Breakdown of primary minerals and formation of secondary minerals; textures indicating alteration; gain and loss of chemical elements during alteration; oxidation.

Week 8: Practical preparation: Al2SiO5 polymorphs
Review of polymorphism; atomic structure, bonding and geological significance of Al2SiO5 polymorphs; relationship between staurolite and Al2SiO5 polymorphs.

Week 9: Practical preparation: Introduction to extinction positions and angles
Straight extinction, as in biotite and hypersthene; inclined extinction as in in augite and hornblende, symmetrical extinction in augite, hornblende and olivine.

Week 10: Practical preparation: Becke line test and mineral identification key
Positive and negative relief in theory; how to detect Becke lines in thin section and deduce positive or negative relief; how to construct a mineral identification key for use in final exam.

Week 11: Practical preparation: Determining plagioclase composition
Introduction to plagioclase composition in theory; how to determine plagioclase composition in thin section.

PRACTICAL CLASSES: (2 hours except where stated)

Practical 1: Description of granite minerals in hand specimen and thin section.
Description of granite minerals (quartz, plagioclase, microcline, biotite, muscovite) in hand specimen; systematic description of the optical properties of minerals in granite in thin section.

Practical 2: Systematic description of augite and hornblende in thin section and hand specimen; how to distinguish between them. Introduction to virtual microscope.

Practical 3: (One hour) Description of hand specimen properties, then relating them to virtual microscope thin section properties, for andalusite, kyanite, sillimanite and staurolite.

Practical 4: Review of comparison of properties seen in hand specimen and the virtual microscope last week. Description in thin section of calcite and dolomite in carbonate sedimentary rock. Description of calcite, aragonite and dolomite in hand specimen.

Practical 5: Description in thin section of coarse sand and comparison with the same minerals in granite. Review of online exercises and general discussion for revision.

Practical 6: Systematic description of olivine, serpentinised olivine, serpentine and magnetite in thin section and hand specimen.

Practical 7: Systematic description of staurolite, andalusite, kyanite and sillimanite in thin section.

Practical 8: Systematic description of garnet, hypersthene and epidote in thin section and hand specimen; extinction angle variations amongst common mafic minerals.

Practical 9: Use of the Becke line test to determine sign of optical relief in muscovite, orthoclase and quartz; description of orthoclase in hand specimen and thin section. Review of mineral keys.

Practical 10: Plagioclase composition determination using the virtual microscope; plagioclase composition determination combined with Becke line test to determine composition of sodic plagioclase. General discussion for revision.

Not applicable to this module.

• Feedback individually to students, on an activity or draft prior to summative assessment
• Group/class feedback, post-assessment
• Self-assessment activities

Written feedback will be provided on practical work, supplemented by oral feedback to the entire class on commonly encountered difficulties. Students will be able to assess their understanding of theory through online self-assessment quizzes.