Diploma in Diamond Grading (D.D)



Duration3 1/2 Months
New Batch CommencesJanuary, April, August, every year. (Tentative Dates)
Timings10.00 a.m. to 1.00 p.m.
Tuition Fee
Seminar Fee
Lab Deposit (Refundable)
Minimum QualificationMatriculation or equivalent (Completion of Gemmology Course D. G; and/or F.G.A. (London); G.G. (USA); D.Gem. G. (Germany) is preferred).
Medium of InstructionEnglish
Attendance100% in practicals and 80% in theory is compulsory.
ExaminationsTheory, Oral and Practical.
Percentage of PassingMinimum 70% in theory/oral examination and 100% in practical examination. Home work assignments and weekly tests will also be taken into account. 90% and above in theory and 100% in practicals qualify for a distinction.
Re-examinationUnsuccessful students wishing to re-appear for the next examination will have to pay the examination fee of Rs. 1,000/-.
CertificateOn successful completion of the course a Diploma is awarded.


CHEMICAL COMPOSITION : Different forms of carbon (graphite, amorphous, diamond)

GEOLOGICAL OCCURRENCES AND THEIR HISTORY : Gem and industrial diamond, kimberlite (mines); Alluvial deposits (river beds); Marine deposits (beaches, sea-bed); Meteoric diamonds; Localities like Australia; Borneo; Brazil; India; Sierra Leon, Russia; South Africa; South West Africa, Zaire, Canada etc.

EXTRACTION OF DIAMONDS : Crushing, Washing and Screening, Heavy media separator; Grease table, Grease belt, X-ray separation

OPERATION OF THE MARKET : De-Beers consolidated Mines; Diamond Trading Company (D.T.C.); Sights supplied by D.T.C.; Diamond Bourses; Clubs; Operation of the National and International markets. Sources of Rough diamonds : HDC, MMTC, NMDC, Local-resellers, DTC, Open market

OPTICAL PROPERTIES : Single; double and anamolous double refraction, Refractive index; Strain patterns; Dispersion; Absorption spectra; Transparency to Ultra-violet and x-rays; Reflectivity; Luminiscence

SORTING OF ROUGH DIAMONDS : Sorting by Size; Shapes; Colour; Purity

HISTORY OF CUTS : The modern brilliant cut; Variation of the brilliant cut; Principles of diamond cutting; Lustre, brilliance, fire, ideal cuts and proportions; variation from the ideal cut

MANUFACTURING OF DIAMONDS : Grains; Sawing; Cleaving; Bruting; Grinding; Polishing; 4,3,2, point stones; Acidising; Ultrasonic cleaning

COLOUR GRADING OF POLISHED STONES : Lighting standards and magnification; Comparison stones. Colour grading systems (G.I.A.; HRD; Indian; C.I.B.J.O.)

CLARITY GRADING OF POLISHED STCNES : Magnification; Lighting; International grading scales; (G.I.A.; HRD; Indian; C.I.B.J.O.); Criteria for grading; Internal blemishes; External defects

GRADING FOR CUT : Spread stones; Lumpy and Fish-eye stones, Proportion scope and proportion analysing, Carat system; Weighing scales; Estimating weight of mounted stones (gauges); Sieves and sieve sizes.Estimating : Table percentage, Pavilion depth, Crown angle, Pavilion angle and Girdle thickness

SYNTHETIC DIAMOND : Synthesis; Artificial colouration; Identification of treated diamond

IDENTIFICATION OF DIAMOND : With 10x only; With Instruments; Type; Classification

DIAMOND SIMULANTS : Gadolinium Gallium Garnet (GGG); Yttrium Aluminium Garnet (YAG); Strontium Titanate; Synthetic Rutile; Synthetic Cubic Zirconia; Synthetic moissanite; Spinet; Sapphire; Zircon; Topaz; Quartz; Paste; Doublets

PRACTICALS : Clarity Grading, Yield estimation and planning of Rough Diamonds, Clarity, Cut and Colour grading of polished diamonds

Short Term



(Applicable for a batch of minimum 2 students)
Duration : 30 hours – 10 days
Days : Mon – Fri.
Timings : 2.30 pm – 5.30 pm (daily 3 hours for 10 days) (Monday to Friday)


  1. Introduction to rough diamond assorting and its importance
  2. Sorting Systems : The Classification of rough diamonds
    • Gem diamond – Near Gem diamond – Industrial diamond
    • Makeable – Sawable – Cleavables
  3. External Features of a rough diamond :
    • Shapes
    • Twin Crystals
    • Combination of forms
    • Surface Markings
    • Other relevant features
  4. Internal Features of a rough diamond :
    • Inclusions found in diamonds
    • Indian Terms for inclusions
    • Colour
    • Cut / Shape
    • Yield
    • Expected Inclusions after Cutting and Polishing
    • Grade
  5. Planning of Rough Diamonds :
    • RBC
    • Fancy
    • Sawables
    • Cleavables
    • Calculation of yield in rough and price per carat of cut and polished diamonds.
    • Understanding the manufacturing process from rough to finish
  6. Cleavables, Yield, Makeables – Practical
    • Clean
    • Operation Clean
    • Fine Inclusions
    • Medium Inclusions
    • Heavy Inclusions
    • Flat
    • Fancy
    • Rejection
    • Natts
    • Mix Stones
    • Sawables
    • Cleavables


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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