Gemmology /
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| Author / Creator: | Read, Peter G. |
|---|---|
| Edition: | Pbk. ed. |
| Imprint: | Oxford ; Boston : Butterworth-Heinemann, 1995. |
| Description: | 358 p. : ill. (some col.) ; 24 cm. |
| Language: | English |
| Subject: | |
| Format: | Print Book |
| URL for this record: | http://pi.lib.uchicago.edu/1001/cat/bib/2344769 |
Table of Contents:
- Preface
- Acknowledgements
- 1. Introduction
- The evolution of the science of gemmology
- Highlights of the last 160 years
- The essential qualities of a gem material
- Organic and inorganic gems
- 2. The geological formation and occurrence of gemstones
- The Earth's structure
- Minerals and rocks
- The formation of gemstones in the Earth's crust
- Groups, species and varieties
- The major gem occurrences of the world
- Mining techniques
- 3. The chemical composition of gemstones
- Atoms, elements, molecules and compounds
- Valency
- Bonding
- The relationship between chemical composition and durability
- 4. Crystallography
- Crystalline and non-crystalline materials
- The atomic structure of a crystal
- Classification of crystals by symmetry
- The seven crystal systems and their elements of symmetry
- Crystal forms
- Crystal habits and their use in identification
- Twinned crystals
- Polycrystalline and microcrystalline minerals
- Metamict minerals
- Defining crystallographic features by indices
- 5. Cleavage, parting and fracture
- The mechanism of cleavage
- Lapidary problems caused by cleavage planes
- The use of cleavage in the fashioning of diamond
- Parting (false or pseudo-cleavage)
- Fracture and its use as an aid to identification
- 6. Hardness
- The durability of a gemstone
- Mohs' scale of comparative hardness
- Hardness tests (using hardness pencils and plates)
- Directional hardness
- Engineering hardness tests
- The influence of hardness on mining techniques
- 7. Specific gravity, density and relative density
- Definitions
- Archimedes' principle and the measurement of SG
- Measurement of SG by displacement
- Hydrostatic methods of SG measurement
- Approximation of SG using heavy liquids
- Safety precautions
- Precise measurement of SG using heavy liquids
- 8. Colour, lustre and sheen
- The electromagnetic spectrum
- The photon
- Colour and selective absorption
- Allochromatic and idiochromatic gems
- The transition elements
- Colour-change gemstones
- Interference colours
- Dispersion
- Colour centres
- Lustre
- Sheen
- Colour, transparency and identification
- 9. Reflection and refraction
- Snell's laws of reflection and refraction
- Refractive index
- Double refraction
- The refractometer
- Contact fluid
- Sources of illumination
- Using the refractometer
- Optic axes, optic sign and optical character
- Distant vision method
- Special refractometer versions
- Fresnel's reflectivity equation
- The reflectance meter
- Other methods of RI measurement
- 10. Polarization and pleochroism
- The polarization of light
- Polarizing filters
- The polariscope
- Using the polariscope
- The conoscope (interference figures)
- Pleochroism (differential selective absorption)
- The dichroscope
- 11. Spectroscopy
- Absorption and emission spectra
- The prism spectroscope
- The diffraction grating spectroscope
- Using the spectroscope
- Fine line spectra
- Fraunhofer lines
- Other spectroscope versions
- Raman spectroscopy
- Spectrophotometers
- 12. Luminescent, electrical and thermal properties of gemstones
- Luminescence (fluorescence and phosphorescence)
- Photoluminescence and Stokes' law
- Crossed filters
- LW and SW UV radiation
- X-ray radiation
- Photoluminescent properties of gemstones
- Other forms of luminescence
- SW UV transmission test
- Electrical properties
- Thermal conductivity and thermal inertia
- Thermal conductance testers
- 13. The hand lens, microscope and Chelsea filter
- Types of hand lens
- Types of microscope
- Light-field, dark-field and incident illumination
- Pin-point illumination and shadowing techniques
- Pin-point illumination and shadowing techniques
- Immersion techniques
- Additional uses for the microscope
- Care in the use of the microscope
- The Chelsea filter
- Handling gemstones
- 14. Gemstone enhancement
- Foils, colour backing and dyeing
- Implanation
- Heat treatments
- Surface diffusion
- Irradiation methods
- Glass filling
- Laser drilling of diamond
- Disclosure of enhancements
- 15. Synthetic gemstones and gemstone simulants
- A brief history of early gemstone synthesis
- Definitions
- The Verneuil flame-fusion process
- The Czochralski method
- Flux-melt growth
- Zone melting
- The hydrothermal process
- The skull-crucible process
- Diamond synthesis
- 'Synthetic' lapis lazuli, turquoise and opal
- Synthetic jadeite
- Gemstone simulants
- Composite gemstones
- Thin diamond films
- 16. Distinguishing between synthetic and natural gemstones
- Growth lines and colour zoning
- Twinning
- Types of inclusion
- Identification features of natural and synthetic gemstones
- Colour zone diffusion and induced feathers/fingerprints
- Use of the polariscope (identifying synthetic quartz and Verneuil corundum)
- Laboratory equipment and methods
- 17. Identifying inorganic gemstone simulants
- Alexandrite
- Aquamarine
- Diamond
- Additional tests for diamond
- Emerald
- Jade
- Lapis lazuli
- Turquoise
- Opal
- Quartz
- Ruby
- Sapphire
- 18. Organic gem materials and their simulants
- Natural pearls
- Cultured pearls
- Distinguishing natural from cultured pearls
- Imitation pearls and their identification
- Shell
- Amber
- Ivory
- Odontolite
- Tortoiseshell
- Jet
- Coral
- 19. The fashioning of gemstones
- Critical angle
- Cutting styles
- Gemstone polishing
- Lapidary techniques
- Gemstone carving
- Diamond polishing methods
- Diamond grading
- Appendices
- A. Bibliography
- B. The organic gems
- C. The inorganic gems
- D. Man-made gems not occurring in nature
- E. Colour theory
- F. Examination notes and sample examination papers
- G. Gemstone constants
- H. Units of measurement
- I. Table of elements
- J. Table of principal Fraunhofer lines
- K. Gemstone weighing
- Index
