Diploma in Gemmology Course (D.G)


Considering the heavy demand from the industry and general public, short-term courses for the identification of gemstones, and treatments, as well as refresher courses in Gemmology, advanced instrumentation courses, etc. are introduced by the Institute. The courses are from 1 week to 1-month duration. A corporate training program is also undertaken. For course details, contact the course coordinator.


INTRODUCTION : Basic qualities; Chemical composition; Weights and measures.

CRYSTALLOGRAPHY : Nature of crystals; Systems of crystallography; Crystalline and non-crystalline materials; Forms; Habit; Twinning.

OPTICAL PROPERTIES : Colour; Transparency; Visible Spectrum; Light Reflection; Total Internal Reflection; Single and Double Refraction; Dispersion; Polarization; Refractive index and its determination by Refractometer; Reflectivity; Reflectometers.

COLOUR AND CAUSES OF COLOUR : Pleochroism; Interference; Lustre; Sheen; Opalescence; Adularescence; Irridescence; Asterism; Chatoyancy

INSTRUMENTS USED FOR GEM IDENTIFICATION : Jeweler’s Lens; Microscope; Spectroscope; Dichroscope; Chelsea colour filter; Ultraviolet light and X-rays; Polariscope; Refractometer

SYNTHETICS, COMPOSITES AND IMITATION GEMSTONES AND PLASTICS : Different methods of manufacture; Characteristics; Identification

DESCRIPTION OF GEM STONES : The varieties and colours, species, chemical composition and crystal systems, physical properties, special characteristics and provenance of the following gemstones Amber; Andalusite; Apatite; Axinite; Aragonite; Azurite; Benitoite; Beryl Emerald, Aquamarine, Heliodor, Morganite, Goshenite; Calcite; Chrysoberyl : Alexandrite, Cat’s eye; Coral; Corundum : Ruby, Sapphire, Star Ruby/Sapphire; Cassiterite; Danburite; Diamond; Diopside; Enstatite; Epidote; Feldspar Group : Moonstone, Albite, Amazonite, Orthoclase, Plagioclase, Labradorite, Sunstone, Fluorspar; Garnet Group : Almandine; Pyrope, Grossular, Andradite; Spessartite, Uvarovite; Haematite; Howelite; Idocrase; lolite; Ivory; Jadeite; Kornerupine; Kyanite; Lapis Lazuli; Malachite; Nephrite; Obsidian; Odontite; Opal : Fire Opal, White Opal, Black Opal, Water Opal; Pearl : Australian, Venezulean, Black, Blue, Freshwater; Conch, Clam, Cultured, Nucleated, Non-Nucleated, Imitation; Peridot; Phenakite; Prehnite; Pyrites; Quartz : Rock crystal, Amethyst, Citrine, Smoky Quartz; Rose Quartz; Aventurine, Quartz Cat’s eye, Tiger’s eye, Rutilated Quartz; Chalcedony Group : Chalcedony; Carnelian, Chrysoprase, Moss Agate, Onyx, Sardonyx, Jasper, Bloodstone, Rhodochrosite; Rhodonite; Sodalite; Sinhalite; Smithsonite; Sphene; Spinel : Ceylonite, Gahnospinel; Spodumene: Kunzite, Hiddenite; Steatite; Topaz; Tortoiseshell; Tourmaline : Achroite, Rubellite, Indicolite, Turquoise, Variscite; Zircon; Zoisite.

FASHIONING OF GEMSTONES : Procedures, processes and equipment used in cutting of diamonds and other stones. Different styles of cutting. Grading gemstones for quality of cutting

TREATMENT OF GEMSTONES : Dyeing, Coating, Heat Treatment, Irradiation, Waxing, fracture filling, oiling, laser drilling, HPHT, diffusion, mass diffusion, graphitisation, composite stones, glass filling

OCCURRENCES OF GEMSTONES : Geographical origin of gemstones is an important aspect in the assessment of quality of gemstones especially Rubies, Sapphires and Emeralds

Electrical and Magnetic properties of gemstones, conductometer.

Thermal conductivity and Thermal probes

Marketing aspects : Gem & Jewellery industry an overview, analysis of prospects and problems of various sectors such as precious/semi precious, diamonds, pearls, synthetic, imitation, jewellery studded and plain gold

Export procedures and formalities


Observation of external features (cut, colour, fractures, etc.) of a gemstones using a 10x lens

Observation of external symmetry, surface marks and cleavage of various crystals and their identification

Determination of hardness on Moh’s Scale using hardness pencils and hardness plates

Determination of specific gravity by hydrostatic weighing method and by using heavy liquids

Measurement of refractive indices and birefringence tests using a gem-testing refractometer

Detection of double refraction, interference figures and internal strain with the polariscope

Detection of double refraction, by observing pleochroic colours with the dichroscope and 10x lens. Identification of gemstones on the basis of pleochroic colours

Study of the absorption spectra of various gemstones using a direct vision spectroscope

Study of the fluorescent colours exhibited by various gemstones under ultraviolet (long wave and short wave) light

Observation of the internal features of various natural and synthetics gemstones with a microscope

Use of colour filters in detecting synthetic gemstones

Identification of unknown gemstones using the above techniques. During the course each student individually practices and handles hundreds of gemstones

An exposure to Advanced instruments such as Raman Spectroscope, FTIR, UV-VIS Spectrophotometer, Fluorimeter, Diamond View etc.

Visual Identification of various gemstones by its crystal system and other external properties;

Various types of cuts and introduction to how to cut gemstones

Detection of treatments on gemstones

Determination of origin of gemstones


Project Works

Field Trips

Quiz / Seminar


Duration3 1/2 Months
New Batch CommencesJanuary, April, August every year
Timings10.00 a.m. to 2.00 p.m.
Tuition Fee
Examination Fee
Seminar Fee
Handbook, Certificate &
Convocation charges
Lab Deposit (Refundable)
Registration FeeStudents willing to register their names in advance for the
Gemmology Course or any other courses conducted by the institute may pay the full fees in advance and confirm their admission. However, after registration, due to unavoidable circumstances, if any one wants to cancel the admission may inform the institute in writing, giving minimum of 20 days notice about their intention to cancel the admission and in such cases the full fees shall be refunded to the applicant.Whereas, it may please be noted that the fees shall not be refunded if the Institute is not informed about the cancellation of admission in writing 20 days prior to the commencement of the classes. After the commencement of the classes Fees shall not be refunded under any circumstances.
Minimum qualificationMatriculation or equivalent
Medium of InstructionEnglish
Home workTheory and objective home work assignments are to be compulsorily completed as per the schedule. At least 2 hours of reading of relevant books and materials are expected per day. Home work assignment marks will be counted for qualifying in the examination.
Project workStudents have to complete a project to qualify for the examinations.
SeminarGemmological Institute organizes seminars of gemmological interest. Attendance at seminar is compulsory.
JournalStudents have to submit a completed journal to qualify for the examinations.
Attendance100% in practical and 80% attendance in theory is compulsory.
LaboratoryA sum of Rs. 1,000/- is charged to every student for the use of the Laboratory / Instruments.
ExaminationTheory, Oral, Practical
Theory3 hours
Practical2 hours
Crystallography and Viva1 hour
LibraryStudent are expected to make use of the Library facility available at the Institute. A sum of Rs. 1,000/- is charged towards the Library fees.
Percentage of PassingMinimum 70% in theory and oral examination; 100% in Practical examination; 90% and above in theory and 100% in practical qualify for a distinction. Home work assignment and weekly tests will also be taken into account.
Re-examinationUnsuccessful students wishing to re-appear for the next examination will have to pay the examination fee of Rs.
CertificateOn successful completion of the course a Diploma in Gemmology. (D.G.) is awarded and such successful students can use the title “D.G.” (Diploma in Gemmology) after their name.
Boarding and LodgingStudents shall have to make their own arrangements for Boarding and lodging in Mumbai.

Short Term


Hands on Practical Approach with theory for clarity in concepts


Distance Education

DIPLOMA IN GEMMOLOGY (D.G.) (Gemmology Correspondence Course) HOME STUDY PROGRAMME

DurationOne Year
New Batch CommencesJanuary, every year, however as special case students may be enrolled during the year.
Minimum QualificationMatriculation or equivalent
Medium of InstructionEnglish
Home work AssignmentsHome work assignments form the first part of the course – 11 essay assignments and 29 objective assignments which should be completed and submitted to the Institute as per schedules in the time table. Home work assignment marks will be counted for qualifying in the examination.
PracticalsPractical training forms the second part of the course. The practicals at the Institute will be for 15 days, full day sessions are held every day. The practicals and the examinations for the correspondence course are held only in the month of December every year.
Boarding and LodgingStudents shall have to make their own arrangements for boarding and lodging in Bombay. Students are allowed to take up practical training and examinations within 3 years from the year of enrollment.
Fees are to be paid in advance as per the following Schedule :-
Tuition fees (Practicals only)on or before 30th Oct. and Examination Fees
LibraryOnly the reference section of the Library will be made available to the students. No home issue of books will be made.
SyllabusSyllabus is exactly the same as that of the residential course (see the Gemmology Resident Programme of the Institute)
ExaminationsTheory, Oral and Practical Examinations will be held once in a year. Generally it will be held in the month of December every year. Without attending practical training at the Institute, students will not be allowed to appear for the practical examinations.
LibraryStudent are expected to make use of the Library facility available at the Institute.
Practical ExaminationUsing the Instruments at the Institute, students are expected to find out the properties of a gemstone and identify a given number of gemstones within a given time. In addition, visual identification of various gemstones, by its crystal system and other visual properties also form a part of the examination.
Theory Examination3 hours
Practical Examination2 hours
Crystallography and Viva1 hours
Percentage of PassingMinimum 70% in Theory/Oral examination and 100% in practical examination; 90% and above in theory and 100% in practical qualify for a distinction. Home work assignments and weekly tests will also be taken into account.
Re-ExaminationUnsuccessful students wishing to re-appear for the next examination will have to pay the examination fees of Rs. 1,000/-.
CertificateOn successful completion of all the above examinations the students (Gemmology Resident/Home study) will be awarded the Diploma in Gemmology – “D.G.”.
Reference Books
  • Gems – by Robert Webster / Anderson
  • Gem Testing – by Basil W. Anderson
  • Beginners Guide to Gemmology by Peter G. Read
  • Handbook of Gem Identification by Richard T. Liddicoat
  • Gemstones – Properties and Identification – by K. T. Ramchandran and Jayshree Panjikar.

The first Research & Development Laboratory in the field of Gemstones in India recognized by the Department of Science & Technology, Government of India as SIRO.

Work Hours

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