Just found this on the ABC News website and found it interesting.
“An Australian mining company says it is using Russian technology to make opals easier to find.
Midnight Opals says the technology can detect objects up to 500 metres underground compared with about 25 metres using previous methods.
Company official Anthony Melonas says it is in partnership with Russian scientists who have developed the geo-radar equipment.
“One of the main things that’s been holding opal back is the fact that opal’s a very hard gemstone to find and now that we can use this geo-radar, we can locate the opal a lot faster – that’s less harmful to the environment,” he said.
“We can get access to land a lot easier – instead of going on there with a drilling rig, we can go on there with this non-invasive technology and we can hit opal right on the pocket instead of drilling holes everywhere and this will go through the whole mining industry.”
(Sourced – http://www.abc.net.au/news/stories/2009/06/22/2604827.htm – June 24, 2009)
This is all well and good, but in our experience (and please take this as opinion) but opal found lower than 30 metres or so, is generally ‘too wet’ (basically has too much water content and thus much more prone to a higher rate of dehydration once taken out of the ground, which can lead to cracking or hazing). So having this super-equipment that can search 500 metres sounds pretty cool, but in theory is no better than the “old” technology used.