Opals! Photonic crystals! Structural color! Opals are examples of natural photonic crystals. They are composed of small silica nanoparticles ranging in size from 50-300nm, and packed tightly together ...

Opals may have been around for thousands of years, but they’re having a major resurgence in the jewelry world right now.

Opals are unique gemstones known for their vibrant colors ... revealing that it consists of different types of nanospheres and has a poorly crystalline nature. Using synchrotron X-ray diffraction ...

When the holy water accidentally splashes her opal hair clasp, the stone fades to black ... but married a different woman, Mercedes of Orleans. According to The Court Jeweller, the countess ...