Course Syllabus

DIPLOMA IN GEMMOLOGY SYLLABUS

Duration: 15 weeks
Days: Mon – Fri
Timings: 10:00 to 02:00 pm

COURSE CONTENT

1. Introduction of gems:
a. Basic qualities;
b. Chemical composition;
c. Weights and Measures.

2. Chemical Composition

3. Crystallography of gemstones
Nature of Crystals: Systems of Crystallography; Crystalline and non Crystalline Materials; Forms; Habit; Twinning.

4. Physical Properties:
a. Hardness
b. Cleavage
c. SG

5. Optical properties:
a. Colour;
b. Transparency;
c. Visible Spectrum;
d. Light Reflection;
e. Total Internal Reflection; Single and Double Refraction;
f. Dispersion;
g. Polarization;
h. Refractive index and its determination by Refractometer; Reflectivity; Reflectometers.

6. Causes of colour in gemstones:
Pleochroism; Interference; Lustre; Sheen; Opalescence; Adularescence; Irridescence; Asterism; Chatoyancy.

7. Use of instruments such as:
Jeweller’s Lens; Microscope; Refractometer; ; Polariscope; Dichroscope; Chelsea Colour Filter; Ultraviolet light, Spectroscope;.Weighing scale and mm gauge.

8. Differentiating Natural Gemstones from Its Synthetics and Simulants
Different Types of Synthetics & Its Identification

9. Description of Gem Stones:
The varieties and colours, species, chemical composition and crystal systems, physical properties etc

Special characteristics and provenance of the following gemstones:
1. Beryl: Emerald, Aquamarine, Heliodor, Morganite, Goshenite; Calcite;
2. Chrysoberyl: Alexandrite, Cat’s eye; Coral
3. Corundum: Ruby, Sapphire, Star Ruby/Sapphire; Cassiterite; Danburite; Diamond; Diopside; Enstatite; Epidote
4. Feldspar Group: Moonstone, Albite, Amazomte, Orthoclase, Plagioclase, Labradorite, Sunstone
5. Garnet Group: Almandme, Pyrope, Grossular, Andradite, Spessartite, Uvarovite
6. Tourmaline: Achroite, Rubellite, Indicolite
7. Chalcedony Group : Chalcedony Carnelian, Chrysoprase, Moss Agate, Onyx, Sardonyx; Jasper; Bloodstone; Rhodochrosite; Rhodonite; Sodalite; Sinhalite; Smithsonite; Sphene
8. Spinel: Ceylonite Gahnospinel
9. Spodumene: Kunzite, Hiddenite
10. Opal: Fire Opal, White Opal; Black Opal, Water Opal
11. Pearl: Natural Marine, Freshwater, Gastrapods; Cultured, Nucleated, Non-Nucleated, Imitation;
12. Quartz: Rock crystal, Amethyst, Citrine, Smoky Quartz, Rose Quartz, Aventurine; Quartz Cats eye, Tiger’s eye, Rutilated Quartz, etc..

And other Gemstones mentioned below :
Haematite ; Howelite; Iodocrase; lvory; Jadeite; Kornerupine ; Amber; Andalusite; Apatite; Axinite; Aragonite; Azurite^Benitoite Kyanite; Lapis Lazuli; Malachite; Nephrite; Obsidian; Odontite; Fluorspar;   Peridot; Phenakite; Prehnite; Pyrites; Steatite; Topaz; Tortoiseshell; Turquoise; Variscite; Zircon; Zoisite.

10. Different types of treatments on gemstones: Heat treatment, glass filling, diffusion etc.

11. Identification of treated gemstones

12. Identification of various inclusions in gemstones by occurrences

13. Marketing aspects of gemstones & export procedures:
a. Gem & Jewellery Industry An Overview, Analysis Of Prospects And Problems Of the Industry
b. Sectors Such As Precious / Semi Precious, Diamonds, Pearls, Synthetic, Imitation, Jewellery
c. Studded and Plain Gold and Formalities.

14. Fashioning of Gemstones:
a. Processes and Equipment Used In Cutting of Diamonds and Other Stones.
b. Different Styles of Cutting.
c. Grading Gemstones for Quality of Cutting.

15. Electrical and Magnetic properties of gemstones, conductometer.

16. Thermal conductivity and Thermal probes.

17. Practicals:
a) Observation of external features (cut, colour, fractures, etc.) of a gemstone using a “10x lens;
b) Observation of external symmetry, surface marks and cleavage of various crystals and their identification;
c) Determination of specific gravity by hydrostatic weighing method
d) Measurement of refractive indices and birefringence tests using a gem-testing refractometer;
e) Detection of double refraction, interference figures and internal strain with the polariscope;
f) Detection of double refraction, by observing pleochroic colours with the dichroscope and 10x lens. Identification of gemstones on the basis of pleochroic colours;
g) Study of the absorption spectra of various gemstones using a direct vision spectroscope;
h) Study of the fluorescent colours exhibited by various gemstones under ultraviolet (long wave and short wave) light;
i) Observation of the internal features of various natural and synthetics gemstones with a microscope;
j) Use of colour filters in detecting synthetic gemstones;
k) Identification of unknown gemstones using the above techniques. During the course each student individually practices and handles hundreds of gemstones;
l) Visual Identification of various gemstones by its crystal system and other external properties;