Fiordaliso 80-Index Faceting Diagram: Precision Gem Cutting Guide
The Fiordaliso is an advanced 5-fold mirror-image symmetry faceting diagram designed for an 80-index gear. Optimized for a Refractive Index (R.I.) of 1.620, it works wonderfully for Tourmaline, Spinel, and Sapphire.
1. Design Overview & Suitable Gem Materials
Calculated for an R.I. of 1.620, this version of Fiordaliso is ideal for Tourmaline and higher R.I. materials, making stunning cuts in blue spinel or sapphire.
2. Technical Design Specifications
- Design Name: Fiordaliso (80 Index)
- Required Index Gear: 80 Index Gear
- Optimized Refractive Index (RI): 1.620 (Tourmaline and higher)
- Facet Count: 86 Facets + 10 Girdle Facets = 96 Total Facets
- Symmetry Type: 5-fold, mirror-image symmetry
- Length-to-Width (L/W): 1.051
- Table-to-Width (T/W): 0.392
- U-to-Width (U/W): 0.372
- Pavilion Depth Ratio (P/W): 0.453
- Crown Height Ratio (C/W): 0.146
- Volume Ratio (Vol./W³): 0.229
3. Cutting Instructions & Angle Sequence
PAVILION CUTTING SEQUENCE
| Facet | Angle | Index Settings (80 Index) | Instruction |
|---|---|---|---|
| 1 | 42.12° | 80-04-08-12-16-20-24-28-32-36-40-44-48-52-56-60-64-68-72-76 | Centerpoint |
| 2 | 90.00° | 80-16-32-48-64 | Set stone size |
| 3 | 90.00° | 08-24-40-56-72 | Leave 1 facet and meet 1 |
| 4 | 62.16° | 08-24-40-56-72 | "Barion" facets (level girdle) |
| 5 | 40.87° | 02-06-10-14-18-22-26-30-34-38-42-46-50-54-58-62-66-70-74-78 | 1/2 facets will meet 4. Cut to centerpoint |
| 6 | 39.00° | 80-08-16-24-32-40-48-56-64-72 | Meet 1 |
CROWN CUTTING SEQUENCE
| Facet | Angle | Index Settings (80 Index) | Instruction |
|---|---|---|---|
| A | 44.00° | 08-24-40-56-72 | Set girdle thickness |
| B | 30.48° | 04-12-20-28-36-44-52-60-68-76 | Meet girdle |
| C | 13.85° | 08-24-40-56-72 | Meet A |
| D | 9.00° | 08-24-40-56-72 | Meet B |
| E | 32.32° | 80-16-32-48-64 | Meet D, level girdle |
| F | 0.00° | Table | Floating |
4. Practical Lapidary & Cutting Tips
- High RI Optimization: Tailored for R.I. 1.620 and above, making it an exceptional option for high-index stones like tourmaline, blue spinel, or sapphire.
- Barion Facets: Pay close attention to facet 4 to properly establish the barion-style leveled girdle structure.
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