On this page:

Overview

When there is an extra facet adjacent to the girdle, there are OLD and New methods to handle them, that define different shapes of the corresponding girdle curve. Later, the points related to the calculation of the stone heights will be searched on this curve. As the different versions of the program use different methods, it is important to understand difference between them.

  • In versions up to 5.2.10 - Girdle bezelGirdle boneand Girdle valley are calculated using the OLD method. NEW method values are also calculated for testing purposes, but available only via the Export Report Data function.
  • Starting from version 5.2.10 - the  Girdle bezeland Girdle bone are calculated using the NEW method. The Girdle valley is calculated using the OLD method.
Girdle Heights Calculation Methods

OLD Method

NEW method

image2019-8-30_13-10-54.png

image2019-8-30_13-11-37.png

Notes

  • extra facet adjacent to the girdle and meeting at least one of the conditions:
    • with height > 10% from Total Height
    • from pavilion side, with facet area > 1/580 from the total cut area
    • from crows side, with facet area > 1/900 from the total cut area
      ...is not a girdle extra facet (it is a crown or pavilion extra facet)
  • steep girdle extra facet has less than 15° deviation from the girdle plane
  • shallow girdle extra facet - more than 15°
  • Uses real model:
    • steep girdle extra facets are calculated as a part of a girdle
    • shallow girdle extra facets are not calculated as a part of a girdle
  • Uses virtual model built on the real brilliant model by:
    • leaving steep girdle extra facets in their places and calculating them as a part of a girdle
    • excluding shallow girdle extra facets
    • excluding caverns
    • for RBC, in all HPO versions except 5.2.10 - excluding crown and pavilion extra facets adjacent to the girdle
    • when excluding a facet, the neighboring facets are continued until they intersect

See examples and further explanations on the Building Virtual Model page.



The following parameters are calculated differently:

For these parameters, the normal bookmark set is extended with the same bookmarks with _GIA (OLD method) and _OCT (NEW method) in their names.

This functionality is currently available only under the following HASP keys:

  • "Developer" HASP key
  • 7-30542
  • 7-30546

For example,

  • GIRDLE_WIDE_BEZEL_MAX
  • GIRDLE_WIDE_BEZEL_6
  • GIRDLE_WIDE_BEZEL_MAX_GIA
  • GIRDLE_WIDE_BEZEL_6_GIA
  • GIRDLE_WIDE_BEZEL_MAX_OCT
  • GIRDLE_WIDE_BEZEL_6_OCT

Currently, for girdle heights calculation, the GIA method is used, which means all reports and appraisers contain GIA method results.

Therefore, values of default bookmarks are equal to _GIA, that is, for example, GIRDLE_WIDE_BEZEL_MAX = GIRDLE_WIDE_BEZEL_MAX_GIA

Examples

Girdle Bezel Difference Example

Here is an example of how Girdle Bezel is calculated differently using GIA and Octonus methods.

Project File with models for this sample

image2019-8-30_13-21-43.png

See details on how points are found in the "Finding Points" section of the Stone Heights Calculation page.


GIRDLE_WIDE_BEZEL_1_OCT2.87GIRDLE_WIDE_BEZEL_1_GIA2.87GIRDLE_WIDE_BEZEL_MM_1_OCT0.137GIRDLE_WIDE_BEZEL_MM_1_GIA0.137
GIRDLE_WIDE_BEZEL_2_OCT2.5GIRDLE_WIDE_BEZEL_2_GIA2.22GIRDLE_WIDE_BEZEL_MM_2_OCT0.119GIRDLE_WIDE_BEZEL_MM_2_GIA0.106
GIRDLE_WIDE_BEZEL_3_OCT3.35GIRDLE_WIDE_BEZEL_3_GIA3.35GIRDLE_WIDE_BEZEL_MM_3_OCT0.16GIRDLE_WIDE_BEZEL_MM_3_GIA0.16
GIRDLE_WIDE_BEZEL_4_OCT3.21GIRDLE_WIDE_BEZEL_4_GIA3.21GIRDLE_WIDE_BEZEL_MM_4_OCT0.153GIRDLE_WIDE_BEZEL_MM_4_GIA0.153
GIRDLE_WIDE_BEZEL_5_OCT2.66GIRDLE_WIDE_BEZEL_5_GIA2.66GIRDLE_WIDE_BEZEL_MM_5_OCT0.127GIRDLE_WIDE_BEZEL_MM_5_GIA0.127
GIRDLE_WIDE_BEZEL_6_OCT2.58GIRDLE_WIDE_BEZEL_6_GIA2.58GIRDLE_WIDE_BEZEL_MM_6_OCT0.123GIRDLE_WIDE_BEZEL_MM_6_GIA0.123
GIRDLE_WIDE_BEZEL_7_OCT2.64GIRDLE_WIDE_BEZEL_7_GIA2.64GIRDLE_WIDE_BEZEL_MM_7_OCT0.126GIRDLE_WIDE_BEZEL_MM_7_GIA0.126
GIRDLE_WIDE_BEZEL_8_OCT2.99GIRDLE_WIDE_BEZEL_8_GIA2.99GIRDLE_WIDE_BEZEL_MM_8_OCT0.143GIRDLE_WIDE_BEZEL_MM_8_GIA0.143
GIRDLE_WIDE_BEZEL_MIN_OCT2.5GIRDLE_WIDE_BEZEL_MIN_GIA2.22GIRDLE_WIDE_BEZEL_MM_MIN_OCT0.119GIRDLE_WIDE_BEZEL_MM_MIN_GIA0.106
GIRDLE_WIDE_BEZEL_MAX_OCT3.35GIRDLE_WIDE_BEZEL_MAX_GIA3.35GIRDLE_WIDE_BEZEL_MM_MAX_OCT0.16GIRDLE_WIDE_BEZEL_MM_MAX_GIA0.16
GIRDLE_WIDE_BEZEL_AVG_OCT2.85GIRDLE_WIDE_BEZEL_AVG_GIA2.81GIRDLE_WIDE_BEZEL_MM_AVG_OCT0.136GIRDLE_WIDE_BEZEL_MM_AVG_GIA0.134
GIRDLE_WIDE_BEZEL_DEV_OCT0.85GIRDLE_WIDE_BEZEL_DEV_GIA1.13GIRDLE_WIDE_BEZEL_MM_DEV_OCT0.041GIRDLE_WIDE_BEZEL_MM_DEV_GIA0.054

Girdle Bezel values summary:



OCT,%GIA,%OCT,mmGIA,mm
GIRDLE_WIDE_BEZEL12.872.870.1370.137

22.52.220.1190.106

33.353.350.160.16

43.213.210.1530.153

52.662.660.1270.127

62.582.580.1230.123

72.642.640.1260.126

82.992.990.1430.143

MIN2.52.220.1190.106

MAX3.353.350.160.16

AVG2.852.810.1360.134

DEV0.851.130.0410.054


Girdle Bone Difference Example

Here is an example of how Girdle Bone is calculated differently using GIA and Octonus methods.

Project File with models for this sample

image2019-8-30_13-23-33.png

See details on how points are found in the "Finding Points" section of the Stone Heights Calculation page.


GIRDLE_WIDE_BONE_1_OCT3.27GIRDLE_WIDE_BONE_1_GIA3.27GIRDLE_WIDE_BONE_MM_1_OCT0.156GIRDLE_WIDE_BONE_MM_1_GIA0.156
GIRDLE_WIDE_BONE_2_OCT3.57GIRDLE_WIDE_BONE_2_GIA3.57GIRDLE_WIDE_BONE_MM_2_OCT0.17GIRDLE_WIDE_BONE_MM_2_GIA0.17
GIRDLE_WIDE_BONE_3_OCT3.68GIRDLE_WIDE_BONE_3_GIA3.68GIRDLE_WIDE_BONE_MM_3_OCT0.176GIRDLE_WIDE_BONE_MM_3_GIA0.176
GIRDLE_WIDE_BONE_4_OCT3.28GIRDLE_WIDE_BONE_4_GIA3.28GIRDLE_WIDE_BONE_MM_4_OCT0.157GIRDLE_WIDE_BONE_MM_4_GIA0.157
GIRDLE_WIDE_BONE_5_OCT3.84GIRDLE_WIDE_BONE_5_GIA3.84GIRDLE_WIDE_BONE_MM_5_OCT0.183GIRDLE_WIDE_BONE_MM_5_GIA0.183
GIRDLE_WIDE_BONE_6_OCT3.19GIRDLE_WIDE_BONE_6_GIA2.7GIRDLE_WIDE_BONE_MM_6_OCT0.153GIRDLE_WIDE_BONE_MM_6_GIA0.129
GIRDLE_WIDE_BONE_7_OCT3.54GIRDLE_WIDE_BONE_7_GIA3.54GIRDLE_WIDE_BONE_MM_7_OCT0.169GIRDLE_WIDE_BONE_MM_7_GIA0.169
GIRDLE_WIDE_BONE_8_OCT3.29GIRDLE_WIDE_BONE_8_GIA3.29GIRDLE_WIDE_BONE_MM_8_OCT0.157GIRDLE_WIDE_BONE_MM_8_GIA0.157
GIRDLE_WIDE_BONE_MIN_OCT3.19GIRDLE_WIDE_BONE_MIN_GIA2.7GIRDLE_WIDE_BONE_MM_MIN_OCT0.153GIRDLE_WIDE_BONE_MM_MIN_GIA0.129
GIRDLE_WIDE_BONE_MAX_OCT3.84GIRDLE_WIDE_BONE_MAX_GIA3.84GIRDLE_WIDE_BONE_MM_MAX_OCT0.183GIRDLE_WIDE_BONE_MM_MAX_GIA0.183
GIRDLE_WIDE_BONE_AVG_OCT3.46GIRDLE_WIDE_BONE_AVG_GIA3.4GIRDLE_WIDE_BONE_MM_AVG_OCT0.165GIRDLE_WIDE_BONE_MM_AVG_GIA0.162
GIRDLE_WIDE_BONE_DEV_OCT0.65GIRDLE_WIDE_BONE_DEV_GIA1.13GIRDLE_WIDE_BONE_MM_DEV_OCT0.031GIRDLE_WIDE_BONE_MM_DEV_GIA0.054

Girdle Bezel values summary:



OCT,%GIA,%OCT,mmGIA,mm
GIRDLE_WIDE_BONE13.273.270.1560.156

23.573.570.170.17

33.683.680.1760.176

43.283.280.1570.157

53.843.840.1830.183

63.192.70.1530.129

73.543.540.1690.169

83.293.290.1570.157

MIN3.192.70.1530.129

MAX3.843.840.1830.183

AVG3.463.40.1650.162

DEV0.651.130.0310.054


Girdle Valley Difference Example

Here is an example of how Girdle Valley is calculated differently using GIA and Octonus methods.

Project File with models for this sample

image2019-8-30_13-24-53.png

See details on how points are found in the "Finding Points" section of the Stone Heights Calculation page.


GIRDLE_NARROW_1_OCT3.66GIRDLE_NARROW_1_GIA3.66GIRDLE_NARROW_MM_1_OCT0.169GIRDLE_NARROW_MM_1_GIA0.169
GIRDLE_NARROW_2_OCT3.72GIRDLE_NARROW_2_GIA3.72GIRDLE_NARROW_MM_2_OCT0.172GIRDLE_NARROW_MM_2_GIA0.172
GIRDLE_NARROW_3_OCT4.04GIRDLE_NARROW_3_GIA3.88GIRDLE_NARROW_MM_3_OCT0.187GIRDLE_NARROW_MM_3_GIA0.18
GIRDLE_NARROW_4_OCT3.92GIRDLE_NARROW_4_GIA4.6GIRDLE_NARROW_MM_4_OCT0.181GIRDLE_NARROW_MM_4_GIA0.213
GIRDLE_NARROW_5_OCT4.01GIRDLE_NARROW_5_GIA4.01GIRDLE_NARROW_MM_5_OCT0.186GIRDLE_NARROW_MM_5_GIA0.186
GIRDLE_NARROW_6_OCT3.94GIRDLE_NARROW_6_GIA3.94GIRDLE_NARROW_MM_6_OCT0.182GIRDLE_NARROW_MM_6_GIA0.182
GIRDLE_NARROW_7_OCT2.91GIRDLE_NARROW_7_GIA2.91GIRDLE_NARROW_MM_7_OCT0.135GIRDLE_NARROW_MM_7_GIA0.135
GIRDLE_NARROW_8_OCT2.5GIRDLE_NARROW_8_GIA2.5GIRDLE_NARROW_MM_8_OCT0.115GIRDLE_NARROW_MM_8_GIA0.115
GIRDLE_NARROW_9_OCT2.68GIRDLE_NARROW_9_GIA2.68GIRDLE_NARROW_MM_9_OCT0.124GIRDLE_NARROW_MM_9_GIA0.124
GIRDLE_NARROW_10_OCT2.28GIRDLE_NARROW_10_GIA2.28GIRDLE_NARROW_MM_10_OCT0.105GIRDLE_NARROW_MM_10_GIA0.105
GIRDLE_NARROW_11_OCT2.17GIRDLE_NARROW_11_GIA2.17GIRDLE_NARROW_MM_11_OCT0.1GIRDLE_NARROW_MM_11_GIA0.1
GIRDLE_NARROW_12_OCT3.09GIRDLE_NARROW_12_GIA3.09GIRDLE_NARROW_MM_12_OCT0.143GIRDLE_NARROW_MM_12_GIA0.143
GIRDLE_NARROW_13_OCT3.57GIRDLE_NARROW_13_GIA3.57GIRDLE_NARROW_MM_13_OCT0.165GIRDLE_NARROW_MM_13_GIA0.165
GIRDLE_NARROW_14_OCT3.45GIRDLE_NARROW_14_GIA3.45GIRDLE_NARROW_MM_14_OCT0.159GIRDLE_NARROW_MM_14_GIA0.159
GIRDLE_NARROW_15_OCT2.94GIRDLE_NARROW_15_GIA2.54GIRDLE_NARROW_MM_15_OCT0.136GIRDLE_NARROW_MM_15_GIA0.118
GIRDLE_NARROW_16_OCT3.23GIRDLE_NARROW_16_GIA2.09GIRDLE_NARROW_MM_16_OCT0.15GIRDLE_NARROW_MM_16_GIA0.097
GIRDLE_NARROW_MIN_OCT2.17GIRDLE_NARROW_MIN_GIA2.09GIRDLE_NARROW_MM_MIN_OCT0.1GIRDLE_NARROW_MM_MIN_GIA0.097
GIRDLE_NARROW_MAX_OCT4.04GIRDLE_NARROW_MAX_GIA4.6GIRDLE_NARROW_MM_MAX_OCT0.187GIRDLE_NARROW_MM_MAX_GIA0.213
GIRDLE_NARROW_AVG_OCT3.26GIRDLE_NARROW_AVG_GIA3.19GIRDLE_NARROW_MM_AVG_OCT0.151GIRDLE_NARROW_MM_AVG_GIA0.148
GIRDLE_NARROW_DEV_OCT1.87GIRDLE_NARROW_DEV_GIA2.51GIRDLE_NARROW_MM_DEV_OCT0.087GIRDLE_NARROW_MM_DEV_GIA0.116

Girdle Bezel values summary:



OCT,%GIA,%OCT,mmGIA,mm
GIRDLE_NARROW13.663.660.1690.169

23.723.720.1720.172

34.043.880.1870.18

43.924.60.1810.213

54.014.010.1860.186

63.943.940.1820.182

72.912.910.1350.135

82.52.50.1150.115

92.682.680.1240.124

102.282.280.1050.105

112.172.170.10.1

123.093.090.1430.143

133.573.570.1650.165

143.453.450.1590.159

152.942.540.1360.118

163.232.090.150.097

MIN2.172.090.10.097

MAX4.044.60.1870.213

AVG3.263.190.1510.148

DEV1.872.510.0870.116

Related Pages

Write a comment...