
The corundum gem family includes ever popular rubies and sapphires. Our IGS member survey results offer some corundum polishing recommendations.
3 Minute Read
Editor’s Note: Some years ago, the International Gem Society (IGS) conducted a survey of members’ polishing techniques. Here, you’ll find the results for corundum polishing. The corundum gem family includes both ruby and sapphire. Whether you’re just starting to learn the art of gem cutting or just looking for a new way to tackle a problematic gem material, we hope these results provide some useful suggestions.
For more information about the survey or to find results for more gemstones, click here.
Check out these articles for additional recommendations for polishing sapphires and polishing synthetic corundum.
| Laptype | polish | lubrication | votes |
| Ceramic | 50-100k diamond | extender/oil | 44 |
| Tin | 14-100k diamond | water, vinegar/oil | 13 |
| BATT | 50-100k diamond | oil or water | 8 |
| Ceramic | 50-100k diamond | none/alcohol/other | 8 |
| Fast or Last lap | 14-50k diamond | oil/water | 7 |
| Copper | 50-100k diamond | oil | 6 |
| Cast Iron | 100k diamond | baby oil/kerosene/olive oil/extender | 5 |
| Ceramic | 50-100k diamond | water | 4 |
| Zinc | 50k diamond | oil | 3 |
| Corian | 14k diamond | oil | 2 |
| Marine Brass | 50k diamond | oil | 2 |
| Turbofan Corundum | water | 1 | |
| Plexiglass | 14-100k diamond | oil | 1 |
| Mirror Facet | Mirror Facet | water | 1 |
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Editor’s Note: Some years ago, the International Gem Society (IGS) conducted a survey of members’ polishing techniques. Here, you’ll find the results for corundum polishing. The corundum gem family includes both ruby and sapphire. Whether you’re just starting to learn the art of gem cutting or just looking for a new way to tackle a problematic gem material, we hope these results provide some useful suggestions.
For more information about the survey or to find results for more gemstones, click here.
Check out these articles for additional recommendations for polishing sapphires and polishing synthetic corundum.
| Laptype | polish | lubrication | votes |
| Ceramic | 50-100k diamond | extender/oil | 44 |
| Tin | 14-100k diamond | water, vinegar/oil | 13 |
| BATT | 50-100k diamond | oil or water | 8 |
| Ceramic | 50-100k diamond | none/alcohol/other | 8 |
| Fast or Last lap | 14-50k diamond | oil/water | 7 |
| Copper | 50-100k diamond | oil | 6 |
| Cast Iron | 100k diamond | baby oil/kerosene/olive oil/extender | 5 |
| Ceramic | 50-100k diamond | water | 4 |
| Zinc | 50k diamond | oil | 3 |
…

The corundum gem family includes ever popular rubies and sapphires. Our IGS member survey results offer some corundum polishing recommendations.
| Corian | 14k diamond | oil | 2 |
| Marine Brass | 50k diamond | oil | 2 |
| Turbofan Corundum | water | 1 |
| Plexiglass | 14-100k diamond | oil | 1 |
| Mirror Facet | Mirror Facet | water | 1 |

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