How do some Opals glow in the dark?

[ipenned]

I was watching a YouTube video on gemstones and came across a rainbow opal that glows in the dark.

Do these opals glow in the dark by charging the source material so that it emits light, much like how applied glow in the dark (lume) on say, watches, emit light in the dark? The video I watched stopped short of explaining and simply left it by saying that the particular opal gets brighter the darker it gets. I don't think that it's possible for opal to inherently continue to emit light without a light source to charge it. So, after say 24 hours in complete darkness, you'll return to an opal that no longer glows in the dark.

Thanks in advance!

 

[T L]

No stone emits light of it's own without a light source. Opals tend to display more colorplay and look more vivid against a dark background, which is why they're usually photographed that way. It's therefore always best to judge true colorplay on a lighter background.

 

[gemandjewelrylover]

I was watching a YouTube video on gemstones and came across a rainbow opal that glows in the dark.

Do these opals glow in the dark by charging the source material so that it emits light, much like how applied glow in the dark (lume) on say, watches, emit light in the dark? The video I watched stopped short of explaining and simply left it by saying that the particular opal gets brighter the darker it gets. I don't think that it's possible for opal to inherently continue to emit light without a light source to charge it. So, after say 24 hours in complete darkness, you'll return to an opal that no longer glows in the dark.

Thanks in advance!

I don't have an answer, but just by chance, I watched that exact same video today! (10 of the most expensive gems in the world or something like that.) lol
The opal was completely stunning.