Searching For Opal With UV Torch
6 April 2023 by Johno
Categories: Opal Fields | Australian Opal | Opal Treatments
Searching for opal with a UV Torch
I have always wanted to search for opal at night with a UV torch.
Years ago I purchased a UV fluoroescent light and connected it to a battery source and tried it out at Lightning Ridge. No luck.The set up was quite cumbersome and didn't seem to work.
I have watched a few of the Opal Hunter videos showing miners finding nice collections of opals at night using black lights. I always wondered why they didn't just do this rather than buying a lot of machinery and taking up mining for short term. I suspect they didn't really find a lot with the torches.
My next attempt
I looked up ebay and bought a lovely UV torch with mutiple globes which I hoped would work
Here is a photograph.
I didn't bother to do any homework and just assumed it would make opals glow in the dark. It didn't.
Trip to White Cliffs 2022
In 2022 we ended up in White Cliffs for a few days.I spoke to a couple of miners about UV torches and they explained that you have to have special UV torch.
I then went on a night tour arranged by the owners of the Red Earth Opal mine. It cost just $30 and they supplied the appropriate equipment including the correct torches. We prospected in a roped off area where there were no holes. This is obviously a good idea as things take on a different perspective at night and there is no way you would see an opal shaft until you fell into it.
We all found some potch as well as other items which glowed under the UV light.We certainly didn't find a fortune but learnt how to use the torch and search for opal.
What sort of torch should you use.
When I got back to Melbourne I decided to do a bit of research, something I should have done long ago. A miner had told me he bought a Fluromin brand torch and it worked well so I looked up their website and this what I found out.
"A torch suitable for finding fluorescent minerals-including opal- must be filtered with a black filter and for optimal results its wavelength must be 365nm. You also need powerful LED's and with good batteries that are rechargeable. Cheap UV torches are mostly unfiltered and use LED's around 390 nm.Without a filter they emit visible light as well as UV which distorts and overpowers the fluorescent colours."
I then purchased one of their torches online at fluromins.com.au It cost $80 plus postage and included two rechargeable batteries and a charger.
I tried it out on some white opal I had and the opal glowed for about 3 seconds after I removed the light source. This allowed me to discern opal from other rocks. I tried it out on some other fluorescent materials and they really glowed as well. The opal glowed a whitish blue colour for the 3 seconds. Other materials such as cigarette butts really glow brightly.
You will end up picking up up anything that glows and sort it out later.
I tried the torch on black opal but not with any luck.
I haven't tried it out in the opal fields yet but I was told by a miner whose son has one of these torches that he, the son,has been using his torch at Andamooka for the past 12 months and has found enough opal to sustain him over that period .
I can't wait to give it a try.
Johno