Watch a gemcutter work with fluorescent green hyalite opal

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I think the obvious question is…

Does hyalite go with riunite? On ice, that’s nice?


I have finally some real actual high UV fluorescent minerals. I have several things I have found that glows some with low energy UV, like you would get with black light, but it isn’t nearly as dramatic.

Now I just need one of the high energy UV lamps.

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That looks like a candidate for someone to throw away money on and have it cut into a Green Lantern ring face. “In brightest day, in darkest night…”




Sure, sure… cut the kryptonite into the shape of Superman’s emblem. That will fool him.


That was cool. I’ve never faceted opal, I’ve only made flat and domed cabochons with it. My wife and I had a chance to mine some precious opal 30 years ago, in Idaho of all places. It was damned hard work, and I wish that I hadn’t sold all my finished stones and rough a few years later, but I don’t have the lapidary equipment to work it today.

It’s a soft stone and chips kind of easily. Because it’s a hydrated amorphous form of silica its chemical composition is partially made up of water, and it is subject to crazing and cracking if it is allowed to dry out completely or is subjected to too much heat from friction while being cut and ground to shape, and polished.

I like that the material in the video gets its color and fluorescence from uranium, kind of like nature’s Vaseline glass. I got my first longwave/shortwave UV mineralogical specimen lamp when I was 10 or 11. It was $30 in 1970, which is the equivalent of around two hundred bucks today. They weren’t as cheap and common as they are today - and not battery-powered.


It’s too expensive, and opal’s rather fragile. Now, there is such a thing as uranium glass…

And in the same vein, wood can do it too!

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I really like how you think… You could have the power battery with a UV light to make it glow.

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“Slightly radioactive.” Though they are different substances, it brings to mind:


Can’t the opals just be sealed somehow, to prevent damage from age and whatnot?


So, Moriarty has Kryptonite.

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I recently found out about “germicidal” UV lights: they go into the UV-C range, which strike me as a possible decent source of high-UV light for under $20. You’d have to take precautions to avoid retinal burn, but standard glass as shielding should work, right? Might be a decent way to, say, light up high-UV fluorescent materials inside a glass-fronted cabinet, at least for short viewing times. Now to get that T.E.A. UV laser working so I can check if UV-fluorescent crystals “speckle” in any sort of interesting way.

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The ‘germicidal’ lamps will indeed UV with considerable vigor. The downside is that, since their objectives are not aesthetic; they generally don’t do the aggressive filtering of visible light that blacklights do.

This often leaves them with a pretty pronounced blue glow that can swamp the output of what you are trying to coax into fluorescence; though if it can fluoresce it probably will when so treated.

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Could you then filter out some of the wavelengths? Probably not for the 20 bucks range, I assume.

An untreated stone is almost always more valuable and desirous than a treated stone, so it’s usually only bad to mediocre grade gems that would be treated like that. Sometimes vulnerable natural stones are only set in earrings or pendants, because stones set in finger rings are more likely to get knocked into stuff and fracture.

There is actually a process to grind an opal flat and then use optically clear epoxy called Opticon to cement a rock crystal (clear quartz) dome onto it. The two-layer stones are called doublets and the quartz cap serves to both protect the opal layer and magnify the play of color. There are also triplets used with thin, vulnerable slices of opal that adds a layer of backing to it as well. Sometimes precious opal occurs in thin seams that aren’t robust enough to be used for jewelry as-is.

You will often see opal rough stored in small jars of water, which serves to keep it hydrated and show off the play of fire in unpolished stones. People will sometimes coat a vulnerable opal with Opticon without adding a crystal cap, but I’ve never had personal experience with that process.

I don’t know if Opticon-coated stones would take as high of a polish as natural stones or doublets would. There are however plenty of examples of chalk grade turquoise which would be unusable as gem material straight from the ground, which is treated with epoxy or a resin similar to it, under pressure. The chalky material absorbs the resin into itself where it subsequently cures, making the material hard enough to cut and polish without crumbling to dust. The treatment also gives the turquoise a darker, richer color.

People also use the resin method to make “reclaimed” or “reconstituted” opal or turquoise using small and sometimes even sand grain-sized pieces of colorful gemstone material. Those are usually set into channels or cells cut into the surface of jewelry pieces, almost like enamel would be in cloisonne.

Sorry that this ran long, I wasn’t sure how much information you wanted.


I have UV coating on my glasses, but not sure what that all blocks…

But hmmm that is interesting because it may cause different things to glow.

I have two black lights, a 4" model I got at Target of all places and is basically a miniversion of what you would put in your room for posters. The other is flashlight that is I think for things like spotting scorpions. The handful of rocks I have found usually have a soft orange glow in places. One cool rock has this sort of outer layer that doesn’t close, but where it is exposed there is ring that of orange that glows. Another is a fairly large crinoid fossil that glows orange. If I had to guess I am thinking that is calcite glowing, as I know some does.

Some of these rocks I spotted by going through people’s decorative rocks at night and see what shows up.

Like I said I have two samples that don’t glow with my lights at all, but do glow with the proper lamps a bright green or orange.

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Nah man, that was interesting. Thanks!

Is there a special name putting a rough opal in a tiny bottle of water? That sounds cool.


Nope, they just use stuff like old baby food jars - or whatever size they need, if they don’t want to spring for glass specimen jars from a medical or scientific supply house. Nice, small glass specimen jars or bottles are a good way to display small, irregularly-shaped pieces of opal just as specimens however, rather than in jewelry.




Oh, I was thinking of a tiny custom bottle, built into a pendant or bracelet.