WHAT TO EXPECT WHEN SHOPPING AT THE OPAL DEALER
SIZE GUIDE
| Size | Grain Size |
|---|---|
| Coarse | 0.6mm to 1.0mm |
| Fine | 0.3mm to 0.6mm |
| Ultra Fine | 0.1mm to 0.3mm |
| Powder | < 0.1mm |
Why Makers Choose Lab-Grown
| Feature | Glass Opal™ (Lab-Grown) | Natural Opal |
|---|---|---|
| Heat resistant to 900°C | ✔ | ✕ |
| Consistent color & pattern | ✔ | ✕ |
| Batch-to-batch matching | ✔ | ✕ |
| Reliable sizing (graded) | ✔ | ✕ |
| Water stability | ✔ | ✕ |
| Repeatable results | ✔ | ✕ |
| Higher yield for price | ✔ | ✕ |
Note: Natural opal varies widely by origin and treatment. Lab-grown opal is engineered for absolute consistency.
FREQUENTLY ASKED QUESTIONS
Yes. Glass Opal™ is classified as synthetic (lab-grown) opal. It contains an ordered silica (SiO2) sphere lattice that produces play-of-color through Bragg Diffraction, just like natural opal. Unlike polymer stabilized opals, Glass Opal™ is composed of 99% pure silica with no resin content.
No. Glass Opal™ contains no water and no resin filler, so it does not dehydrate, craze, or yellow like natural opal. Its pure silica composition also gives it far greater thermal stability than either natural or resin based opal.
Yes. Glass Opal™ is heat resistant up to approximately 900°C, making it suitable for glasswork, fusing, and torch use with borosilicate glass. Its coefficient of expansion (30.5 to 33) is compatible with standard borosilicate COE, reducing the risk of cracking from thermal shock during glassblowing.
Glass Opal™ contains silica. Use wet methods or appropriate respiratory protection when cutting or grinding to minimize airborne silica exposure.
No. Glass Opal™ is an independent, modern lab-grown opal product and is not manufactured by, affiliated with, or endorsed by Gilson Opal® or any related brand. We use the term "Gilson-like" only to describe a similar style of lab-created opal for buyers familiar with that naming convention, not to claim any origin or brand connection.