In HP Carbon, plans for Brilliant cut are allocated with the "GIA Facetware + My Round" appraiser. GIA Facetware rounds the parameters' values.

In some cases, this rounding may cause a problem: when you finish cutting in precise accordance with the plan and the result is scanned, different scanners (for example, yours and GIA lab) may slightly deviate the scanned model. So if our plan was too close to rounding boundaries, the resulting parameter value after rounding may go outside the EX boundaries to VG, etc. This can cause your EX stone from your scanner perspective will unexpectedly become VG from the GIA lab perspective.

To eliminate this risk, for the Smart Recut algorithm, the Safe Boundaries mode is used.


The mode is intended to be used when working with Brilliant cut. The mode sets safe distances to a possible GIA rounding. The values are:

GRID ParameterMarginUnits
Table0,008mm
Crown angle0,10deg
Pavilion angle0,06deg
Star length1,5%
Lower girdle length1,5%
Girdle bezel0,1%
Example for Crown Angle
A usual SR produced 32.24, it was rounded by GIA to 32.0 which gave ЕХ. When you scanned after cutting, your scanner gave 32.24, but another one (GIA lab?) produced a model with 32.26. This will be rounded to 32.5 and will give VG. Result: lost money.And the Safe Boundaries mode will step out from disputed border 32.25 by 0.1 and will produce plan 32.14 instead of 32.24. This may lead to a little mass decrease (probably even not affecting the price). But you are guaranteed to get an EX GIA grade at any scanner.
Other GIA Cut parametersMarginUnits
Girdle valley Min0,1%
Girdle valley Max0,1%
Culet0,1%
Crown painting0,2deg
Pav painting0,2deg
Sum painting0,2deg

At the moment, these values cannot be changed - in the future, it is planned to provide a user interface for viewing/editing.

The mode is turned on by the Safe Boundaries checkbox.

The mode can be used when running the Smart Recut allocation from Recut solution. However, if you already have a Smart Recut solution previously obtained without using the Safe Boundaries option, it is more effective to run Smart Recut allocation with Safe Boundaries from this previous Smart Recut.

The Table parameter can obtain a value close to the GIA rounding boundary (for example, 58.49%). This means that regardless of rounding up or down (58% or 59%) the required GIA Cut Grade will be produced with other 5 GRID parameters set.


Get GIA cut grade safe plan for Brilliant cut

  1. In the Recut mode, in Plans & Scans, select your recut or smart recut plan that was produced without safe boundaries.
  2. Set Algorithm to Smart Recut.
  3. Select Safe Boundaries.
  4. Click Start Allocation. The Smart Recut plans with safe boundaries are added to the list.
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