How to Read a GIA Diamond Grading Report

Diamond-Grading-Report-300x139

The GIA Diamond Grading Report includes an assessment of the 4Cs – Colour, Clarity, Cut, and Carat Weight – along with a plotted diagram of its clarity characteristics and a graphic representation of the diamond’s proportions. GIA issues the Diamond Grading Report for loose natural diamonds only, weighing 0.15 carats or more. For standard round brilliant cut diamonds falling in the report also includes a GIA Cut grade.

 1. DATE 

Date diamond was examined by GIA.

2. REPORT NUMBER

Unique GIA report number registered in GIA’s extensive global database.

3. SHAPE AND CUTTING STYLE

The outline of the diamond (shape) and the pattern of the facet arrangement (cutting style).

4. MEASUREMENTS

Diamond dimensions listed as “minimum diameter – maximum diameter x depth” for round diamonds and “length x width x depth” for fancy-shaped diamonds.

5. CARAT WEIGHT

Weight given in carats, recorded to the nearest hundredth of a carat. One carat is equal to 1/5 of a gram.

6. COLOUR GRADE

The absence of colour ranging from colourless to light yellow or brown when compared to GIA Master Color Comparison Diamonds. Graded on a D-to-Z scale. If “*” appears next to the colour grade, a colour treatment was detected.

7. CLARITY GRADE

The relative absence of inclusions and blemishes. Graded on a scale from Flawless to Included based on size, nature, number, position, and relief of characteristics visible under 10x magnification.

8. CUT GRADE

For standard, D-to-Z color, round brilliant diamonds. Cut grade incorporates the aspects of face-up appearance, design, and craftsmanship. Graded on a scale from Excellent to Poor.

9. POLISH

Smoothness of the diamond’s surface, assessed on a scale ranging from Excellent to Poor.

10. SYMMETRY

Exactness of the diamond’s outline, and the shape, placement, and alignment of its facets, assessed on a scale ranging from Excellent to Poor.

11. FLUORESCENCE

Strength and color of the diamond when viewed under long-wave ultraviolet light. A fluorescence description of “none” represents a range of fluorescence from Indiscernible to Very Faint. Used for identification purposes.

12. INSCRIPTION(S)

Any text, symbols, logos, or a unique GIA report number inscribed on the diamond’s girdle.

13. COMMENTS

Additional identifying characteristics or features that are not otherwise represented on the report. If a treatment is detected, such as laser drilling, it would be described here.

14. PROPORTION DIAGRAM

Graphic profile representation of the diamond’s actual proportions.

15. PLOTTED DIAGRAM

Approximates the shape and cutting style of the diamond. Symbols indicate the type or nature, position, and the approximate size of a clarity characteristic.

16. KEY TO SYMBOLS

Lists the characteristics and symbols shown on the plotting diagram, if present.

17. GIA COLOUR SCALE

Illustrates the GIA Colour grades and their relative positions in the GIA Diamond Colour Grading System.

18. GIA CLARITY SCALE

Illustrates the GIA Clarity grades and their relative positions in the GIA Diamond Clarity Grading System.

19. GIA CUT SCALE

Illustrates the GIA Cut grades and their relative position in the GIA Diamond Cut Grading System. Available for standard round brilliant cut diamonds in the D-to-Z color range and Flawless-to-I3 clarity range.

20. SECURITY FEATURES

Microprinting, security screens, watermarks, a two-dimensional barcode, a hologram, and sheet numbering safeguard report integrity and facilitate document authentication.

21. QR CODE

A two-dimensional barcode that, when scanned, verifies data on the report against the GIA database.

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s