As a rare and precious variety in jewelry, opal belongs to the emerald family in minerals. Opal is also called cat's eye, cat essence, cat's eye and oriental cat's eye. Opal is called opal because it can shine like the color of cat's eye and change with the intensity of light. This cat's eye effect is an optical phenomenon.

Opal has many colors, such as yellow-green, yellow-brown, honey yellow, brown yellow, wine yellow, gray-green and so on, among which honey yellow is the most precious. Opal always has a brown cat's eye, which can change with the change of light intensity, while fake opal does not have this feature. The natural opal eyeliner is very straight, and the distribution is very balanced, and there is no break. More importantly, this line is very clear and bright, and the fake opal does not have this effect.

Matters needing attention in purchasing opal

1, cat's eye effect: the good opal stone has smooth surface, clear and obvious cat's eye pattern, and the cat's eye effect is remarkable, while the poor opal cat's eye effect is not obvious or has no cat's eye effect.

2. Observe the color: the high-quality opal is bright and pure, with uniform color distribution, while the inferior opal is dim or unevenly distributed.

3. Look at the transparency: a good opal has high transparency, and the cat's eye line can be seen after light penetration, while a poor opal has low transparency, and the cat's eye line cannot be seen after light penetration.

4. Check the scratches: gently scrape the opal with hard objects such as metal objects. If there are obvious scratches on the opal surface, the quality is poor.

5, look at the size of the stone: the size and type of opal will affect the price, you should choose the right opal according to your own needs and economic situation.