The Lippy design is a simple yet elegant oval/navette gem cutting diagram crafted for high-refractive-index gemstones. It is particularly effective for recutting dark stones (such as dark spinel or sapphire) to bring out internal brilliance, lively sparkles, and vivid color play.
Targeted for a Refractive Index of R.I. = 1.720, this 96-index design features 2-fold mirror-image symmetry and delivers an excellent volume-to-width ratio, making it an enjoyable cut for lapidaries of all skill levels.
Design Specifications
| Parameter | Specification Details |
|---|---|
| Design Name | Lippy |
| Target RI | R.I. = 1.720 (Spinel, Sapphire & Higher) |
| Facet Count | 33 facets + 8 girdles = 41 total |
| Symmetry / Index | 2-fold, mirror-image symmetry | 96 Index Gear |
| Proportions | L/W=1.482 | T/W=1.050 | U/W=0.437 P/W=0.441 | C/W=0.176 |
| Volume Ratio | Vol./W³ = 0.344 |
Step-by-Step Cutting Angles
1. Pavilion Cutting Sequence
| Facet | Angle | 96-Index Settings | Instruction / Meet Point |
|---|---|---|---|
| 1 | 44.74° | 04-44-52-92 | TCP (Temporary Centerpoint) |
| 2 | 90.00° | 04-44-52-92 | This sets the stone size |
| 3 | 41.37° | 96-48 | Meet girdle |
| 4 | 40.00° | 12-36-60-84 | Meet 1, 3 |
| 5 | 90.00° | 16-32-64-80 | Meet 1, 4 |
| 6 | 44.74° | 16-32-64-80 | Meet 1, 4, 5 |
2. Crown Cutting Sequence
| Facet | Angle | 96-Index Settings | Instruction / Meet Point |
|---|---|---|---|
| A | 43.24° | 04-44-52-92 | Set girdle thickness |
| B | 43.24° | 16-32-64-80 | Uniform girdle thickness |
| C | 29.84° | 09-39-57-87 | Meet girdle |
| D | 32.00° | 96-48 | Meet girdle |
| E | 16.82° | 06-42-54-90 | Meet A, D, C |
| F | 0.00° | Table | Meet B, C, D, E |
Recommended Gemstones
Although originally designed for Spinel, Lippy works excellently across various medium-to-high RI gemstones:
- Spinel (RI 1.718): Ideal for recutting dark purple, blue, or dark red spinel rough to introduce bright sparkles.
- Sapphire & Ruby (RI 1.762 - 1.770): Excellent choice for oval corundum rough needing maximum light return.
- Garnet & Tourmaline: Works well with materials having an RI higher than Quartz.
Pro Cutting Tips & Insights
- Table Alignment Care: When cutting Table Facet F (0.00°), pay close attention to the meet points around B, C, D, and E. Meets may require slight angle adjustments or micro-tweaks to line up perfectly.
- No Preform Required: Fully meetpoint faceting allows you to cut directly without preparing special L/W preforms in advance.
Looking for more free faceting diagrams and precision gemology tutorials? Explore our full collection on Horizon Gems!
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