Opal mining: If It Glows Do I Want It

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hello all once again....hope i got this in the rite spot... Im using a eagtac 365nm mx30l3-c uv led light which is not a bad black light so im told. My queston is this if i use the blacklight and when i turn it off the spot that i used it on glows for afew seconds is that the stuff opal hunters are looking for ?.
 
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grubstake

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That looks SO dodgy down there, mate - do you actually know what you're doing? Some areas looked like the miners had taken out too much of the roof support rock, but I didn't see a single timber prop in place to take the load.
 
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That looks SO dodgy down there, mate - do you actually know what you're doing? Some areas looked like the miners had taken out too much of the roof support rock, but I didn't see a single timber prop in place to take the load.
Hello and thank you for your reply "Do i know what i am doing ?: No idea at all as for supports i have been advised that it is safe as im am around 12 to 15 mtrs underground and another person who showed me there underground claim is alot wider and higher than mine and they have no supports but have been doing it for 20 years. That is my knowledge of mining.. I got it more as a place to get out of the 45 degree heat instead of sitting at home with the air con going,
 

grubstake

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In your video I could see some big heaps of broken rock that looked like it had fallen from the roof, which would indicate dangerous instability if it has.

I'm not a mining engineer but I've been down a number of underground mines here in WA (and one in California), always accompanied by trusted professionals. I've actually seen an area of a mine that was in the process of shedding overhead rock - the Chief Geologist of a major mining company took me there to show me how it looked. He was hopping over boulders saying encouraging things like, "This material has fallen down since I was here yesterday"! It was damned scary.

Opal mining is full of people who think they know what's what on the basis of practical experience only, rather than actual mining expertise and training. Please take great care.
 
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In your video I could see some big heaps of broken rock that looked like it had fallen from the roof, which would indicate dangerous instability if it has.

I'm not a mining engineer but I've been down a number of underground mines here in WA (and one in California), always accompanied by trusted professionals. I've actually seen an area of a mine that was in the process of shedding overhead rock - the Chief Geologist of a major mining company took me there to show me how it looked. He was hopping over boulders saying encouraging things like, "This material has fallen down since I was here yesterday"! It was damned scary.

Opal mining is full of people who think they know what's what on the basis of practical experience only, rather than actual mining expertise and training. Please take great care.
ah yes i see your point and do thank you for your advice i will look into its safety more
 
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short answer, safety aside, is that only some opal glows under a specific UV wavelength (please correct me if I'm wrong, but I think 265nm?) and it will only work on white opal (again please correct if wrong)
 
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My sum total knowledge of opal mining is from watching Opal Hunters on TV so take this for what it's worth 😃...

When they were using a blacklight, all the white opal type rocks glowed, but they had to look at it again in natural light to pick out the opal with colour, (the good stuff) and sort that from the more common potch ie a bland looking type of opal with no colour and therefore worthless.....I don't recall seeing whether it worked on black opal or not...

Other minerals can glow under a black light, but I wouldn't think they would be common in opal bearing rocks...

As an aside, I have also seen scorpions glowing under a blacklight although that was in RSA, so have no idea if your local varieties do the same...
 
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In your video I could see some big heaps of broken rock that looked like it had fallen from the roof, which would indicate dangerous instability if it has.

I'm not a mining engineer but I've been down a number of underground mines here in WA (and one in California), always accompanied by trusted professionals. I've actually seen an area of a mine that was in the process of shedding overhead rock - the Chief Geologist of a major mining company took me there to show me how it looked. He was hopping over boulders saying encouraging things like, "This material has fallen down since I was here yesterday"! It was damned scary.

Opal mining is full of people who think they know what's what on the basis of practical experience only, rather than actual mining expertise and training. Please take great care.
I had the chance to go down one of the ultra deep goldmines in South Africa, and like you say very scary stuff. The had some sort of drag system on chains bolted to the roof that would drag the mined gold bearing rock from the face...We were standing about 20 yards from the back of this watching a guy operate it when it brought part of the roof down at the mine face...it was only a small collapse and seemed to be business as usual to the miners but scared the crap out of me!
 
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My sum total knowledge of opal mining is from watching Opal Hunters on TV so take this for what it's worth 😃...

When they were using a blacklight, all the white opal type rocks glowed, but they had to look at it again in natural light to pick out the opal with colour, (the good stuff) and sort that from the more common potch ie a bland looking type of opal with no colour and therefore worthless.....I don't recall seeing whether it worked on black opal or not...

Other minerals can glow under a black light, but I wouldn't think they would be common in opal bearing rocks...

As an aside, I have also seen scorpions glowing under a blacklight although that was in RSA, so have no idea if your local varieties do the same...
thank you for your reply. i have met a guy here who was on opal hunters and am hoping to cross paths with him again and will seek some advice on the stuff that ive come across.
 

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short answer, safety aside, is that only some opal glows under a specific UV wavelength (please correct me if I'm wrong, but I think 265nm?) and it will only work on white opal (again please correct if wrong)
About 60% will fluoresce, but perhaps only a third of black opal.

I have rarely seen timber supports underground in operating opal mines. Cannot compare with things like South African gold mines! However even opal mines do become unstable with time and I do not recommend entering old workings without an experienced miner with you to bar loose stuff down.
 

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