Hi IGS,
I’ve just signed up to the website reaching out for an expert opinion on a claim in Canada, BC extracting what I believe (absolute no background in geology/gemology) to be the only source of precious black opal in our province.
Here are some recent finds we have dug out only a few weeks ago (October 2017)
I’m aware about how rare this stone is, but I really don’t have any source of information of how to pursue it. The claim was staked by my grandfather over 15 years ago, who unfortunately passed away not much longer after discovery. He wasn’t a geologist or anything of the sorts, but he dedicated his entire life to rockhounding and had incredible passion for it!
I’ve researched online a little amount and found a 30 page geological report of our claim which my grandfather had a professional assess it. The report is old, and it wasn’t until after it had been created that we found the black stones with color, but has definitely been a very descriptive and informative means of understanding about volcanic activity and other things for me. Perhaps I could release that to someone who is interested about the scientific standpoint of where we are finding our beautiful stones
Here is some information I took out of the geological report
Massive to columnar jointed basalt to andesite-basalt flows
High vesicular [elongate commonly aligned) to amygdaloidal units (20cm+ long)
precious opal occurs in a broad range of base colours including transparent, white, green,
orange and browns. Precious opals display pinfire, mosaic (harlequin) and flash play-of-colour with variable brightness. Colours often include red, green and some blue, local violet. (Opal shows full spectrum of white through to black)
In conclusion to this topic, I’d love to find an expert opinion from someone who knows more about opals as well as mining it. Perhaps someone is out there that can help me identify where it’s coming from? I’m 23 years old and starting at the bottom of the barrel for anything to do with mining. Currently looking into courses for gemology, and would love to learn about lapidary methods!
Thank you for your time
Edit -
Here is some information I can give you about the area
The opal that we have is forming on top of a small mountain. The host rock contents of what we’re mining is VERY hard. (volcanic bedrock) Think of the top of the bluff being a puzzle, as all of the columns of basalt are all twisted and matched in perfectly holding the next rock into it. Extracting a large piece of column can take sometimes hours of hard hammering while also strategically stripping away a piece of the puzzle that will make the next piece easier to move out and so on!
I haven’t seen opal mining coming from large slabs of rock, but I’ve really only watched the australian documentarys. What a difference it is from us to them. What they’re drilling into is sand, and definitely makes a guy jealous when watching them easily chisel into there drillings to create mines haha.
But what I like about the large basalt columns are the fascinating empty vesicles filled with crustaceans all over the place. I know nothing about it, but I believe that the vesicles have a big thing to do with the opal. Sometimes we find the vesicles that aren’t empty which are jampacked full of precious / common opal ranging from pure white through to pure black. It’s indescribably such a fantastic moment when you find one of these huge deposits which some are over 1000 carats large!