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Diamond Measurement:

  • length, width & height measurements
  • depth percentage
  • table percentage
  • girdle thickness
  • culet size
  • crown angle
  • crown height
  • pavilion angle
  • pavilion height
  • diamond symmetry.

The cut of a diamond is made up of many elements. To determine the quality of a diamond's cut gemological laboratories use sophisticated non-contact measuring devices to determine how well a diamond is cut.

The Sarin  DiaMension proportion analyzer is used by GIA and other gemological laboratories to analyze diamond proportions. It currently provides the most accurate evaluation of diamond proportion measurements available today. It is important to know, Sarin Diamension proportion analyzers are factory calibrated to closest possible tolerances, however, measurements are subject to factory calibration variations of plus or minus .02 millimeters on any diamond that is measured by different Sarin proportion analyzers. As a result, these slight variations in proportion measurements can create differences in percentage calculations on applicable elements of proportion.

Sarin proportion analyzers provide these important details about a diamonds proportions: 

Learn how proportions are calculated:

The average diameter of a round brilliant cut diamond would be calculated by obtaining the minimum and maximum diameters and dividing their total by two.

For example:
minimum diameter     6.09
maximum diameter      6.15

The average diameter equals =
6.09 + 6.15 =12.24
12.24 / 2 = 6.12

The table percentage is calculated by determining the average table diameter and dividing it by the diamonds average girdle diameter. Convert the result to percentage ((mulitiply by 100). Round to the nearest one percent.

For example:
average table diameter      3.67 millimeters
average girdle diameter     6.12 millimeters

The table percentage equals =
(3.67 / 6.12) =.59967
.59967 x 100 = 59.96%
rounded to 60%

The total depth percentage, pavilion depth percentage and crown height percentage is calculated by dividing average measurement of each by average girdle diameter. Convert the result to percentage (multiply by 100). Round to the nearest .01% percent.

Certified GIA diamond quality reports but do not provide crown height, crown angles, pavilion depth percentages and pavilion angles. Selecting a diamond without the assurance of these important elements of cut is not advisable.

Donít take chances. Droste's provides all the important diamond proportion details, unmatched quality assurance and lower prices.

Droste's gemological laboratory is equipped with a Sarin Diamension proportion analyzer and is gemologically accredited by the American Gem Society (AGS).

Our Certified Gemologist-Appraisers carefully examine every diamond to ensure that crown height, crown angles, pavilion depth percentage and pavilion angles are within the ranges of ideal to very fine quality before it is shipped to you.

Droste's will not deliver a diamond until cut quality is confirmed to be very fine or ideal cut and all elements of cut are discussed with you.

Donít take chances or waste time. Only Droste's gives you the complete story on diamond quality. Buy your diamond direct from knowledgeable experts you can trust. Our Certified Gemologist-Appraser will be happy to answer any questions you may have in regards to selecting a properly cut diamond.