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FGA Foundation Study Guide

Study guide aligned with the Gem-A Foundation in Gemmology curriculum.

Course Overview

The Foundation course introduces fundamental concepts of gemmology, providing a solid base for practical gem identification and theoretical understanding.

Module 1: Introduction to Gemmology

Learning Objectives

  • Define gemmology and its scope
  • Understand what makes a gemstone
  • Identify the main gem categories

Key Topics

  1. Definition of a Gemstone
  2. Beauty (colour, lustre, transparency)
  3. Durability (hardness, toughness, stability)

  4. Rarity and desirability

  5. Gem Categories

  6. Natural minerals
  7. Organic gems (pearl, coral, amber)
  8. Synthetic and simulant materials

Study Resources

Module 2: Physical Properties

Learning Objectives

  • Understand and measure specific gravity
  • Use the Mohs hardness scale
  • Identify crystal systems
  • Recognize cleavage and fracture

Key Topics

  1. Specific Gravity
  2. Definition and measurement
  3. Hydrostatic method

  4. Heavy liquid method

  5. Hardness

  6. Mohs scale reference minerals
  7. Hardness testing techniques

  8. Durability considerations

  9. Crystal Systems

  10. Seven crystal systems
  11. Symmetry elements
  12. Common gem examples

Practical Exercises

  • Measure SG of 10 unknown gems
  • Identify crystal systems by shape
  • Test relative hardness

Module 3: Optical Properties

Learning Objectives

  • Understand light and colour
  • Measure refractive index
  • Identify optical character
  • Observe pleochroism

Key Topics

  1. Light Behaviour
  2. Refraction and reflection
  3. Dispersion

  4. Absorption

  5. Refractive Index

  6. Definition and significance
  7. Refractometer use

  8. Spot readings vs. full readings

  9. Optical Character

  10. Isotropic vs. anisotropic
  11. Uniaxial and biaxial

  12. Positive and negative

  13. Pleochroism

  14. Dichroism and trichroism
  15. Dichroscope use

Practical Exercises

  • Take RI readings of 20 gems
  • Determine optical character with polariscope
  • Observe pleochroism in tourmaline

Module 4: Gem Testing Instruments

Learning Objectives

  • Master refractometer technique
  • Use polariscope effectively
  • Interpret spectroscope readings
  • Apply Chelsea filter and UV lamp

Instrument Techniques

  1. Refractometer
  2. Calibration check
  3. Faceted stone technique
  4. Cabochon technique

  5. Troubleshooting

  6. Polariscope

  7. Isotropic test
  8. Anisotropic test

  9. ADR and anomalous extinction

  10. Spectroscope

  11. Prism vs. diffraction grating
  12. Setting up and focusing
  13. Recording spectra

Study Resources

Module 5: Inclusions

Learning Objectives

  • Identify common inclusion types
  • Use microscope effectively
  • Recognize diagnostic inclusions
  • Distinguish natural from synthetic

Key Topics

  1. Inclusion Types
  2. Crystal inclusions
  3. Fluid inclusions
  4. Growth features

  5. Fingerprints

  6. Diagnostic Inclusions

  7. Ruby/sapphire silk
  8. Emerald jardín

  9. Garnet inclusions

  10. Natural vs. Synthetic

  11. Curved striae (flame fusion)
  12. Seed plates (hydrothermal)
  13. Flux inclusions

Study Resources

Module 6: Major Gem Species

Learning Objectives

  • Identify major gem species
  • Know key properties for each
  • Recognize varieties

Species Covered

  1. Diamond
  2. Corundum (ruby, sapphire)
  3. Beryl (emerald, aquamarine)
  4. Chrysoberyl (alexandrite, cat's eye)
  5. Garnet Group
  6. Tourmaline
  7. Quartz
  8. Feldspar (moonstone, labradorite)
  9. Topaz
  10. Spinel

Study Resources

Module 7: Treatments

Learning Objectives

  • Understand common treatments
  • Recognize treatment indicators
  • Know disclosure requirements

Key Topics

  1. Heat Treatment
  2. Effects on colour
  3. Detection methods

  4. Disclosure

  5. Filling Treatments

  6. Glass filling
  7. Oil treatment

  8. Resin filling

  9. Surface Treatments

  10. Coatings
  11. Diffusion

Study Resources

Module 8: Synthetics and Simulants

Learning Objectives

  • Understand synthesis methods
  • Identify synthetic indicators
  • Distinguish simulants

Key Topics

  1. Synthesis Methods
  2. Flame fusion (Verneuil)
  3. Hydrothermal

  4. Flux growth

  5. Detection

  6. Curved striae
  7. Gas bubbles
  8. Characteristic inclusions

Study Resources

Exam Preparation

Theory Exam

  • Multiple choice questions
  • Short answer questions
  • Gem identification from descriptions

Practical Exam

  • Identify 10 stones using instruments
  • Written report on each stone
  • Justification of identification

Study Tips

  1. Practice instrument use daily
  2. Build reference stone collection
  3. Create flashcards for properties
  4. Join study groups
  5. Review past papers