Opal Mining Newsletter July-15-03 on Mining Underground for Opals in Coober Pedy

Went to pull the shot, but I saw that some white potch was in the wall, so spent the morning jackpicking the rest of the pocket out, I was hoping that it might turn to color but was not that lucky. (again)

By the time I had finished it was about lunch time and so I packed up and went home, best to leave the hard work for tomorrow, below is a piece that was blown down, as you can see it is very white and you can also see how the opal is formed into individual pieces but at the same time is all joined together, this gives you a better idea how opal is formed and how we get pieces that are of different sizes.

Pulled the shot, but as I had to clean up a bit around the elbow and I did pull a bit of that wet dirt, it was not as wet as I thought so that was a blessing, there is still quite a bit left but will pull that as I explained in last weeks update.

So the job took a lot longer than I expected, 4.5 hours in all, because as I was pulling the dirt and I had reached the shot face, which means the shot itself and not all of the extra dirt that is there from me jackpicking the wall and blowing down the roof, when I get to this shot face, this is when I start looking for any opal or material that has fallen down when the bombs went off.

There was trace (potch or opal which is thin) all along the shot face on the level so I had to check the shot with the pick and the blacklight and then pull some of the dirt and then check it again, this happens until all of the shot has gone, I did pull out of the face some material and at times it showed a bit of green and not knowing if there is going to be a small pocket of opal in there I have to check it all the way, also I have to check the roof that has been blown down to make sure that there is was no vertical in there.

As this ground can produce a pocket of colored opal at any time, I have to be careful that I don't put it up top on the dump and lose it, so it is a slow process when there is a chance of opal around, I will take a photo of the shot face in the next shot to explain what I am talking about here, did not think of it until I was writing this.

Below is a bucket of potch that I am going to give away, I have keep some of the big pieces that might be used in cutting as backs for doublets or for just practicing with, this bucket was full to the top and I had another one that had 30 ounces in, if only this could have been color, it would have been worth a lot of money, one day I will find a pocket of color, crystal no less, that will fill this I hope, then I can retire for good.

I was so tired after yesterdays work that Patricia asked me to stay at home and rest, but I said No as I want to get this shot in, today might just be pay day as there is some trace in the level, thin but trace never the less and who knows what is in front of me.

Below is the new drive No2, we are in 8 foot here, when I started this there was no proper level there just gypsum again, with some small white potch under it in places and you have seen the result of that shot above, now we have a very defined ironstone level again, also there is a small vertical shown here, it has potch from the top to the bottom, so I am very interested to see if this can turn into something better and bigger.

I have put or will put the shots another 3 inches further down from the level, so when the shot goes off hopefully the level will stay where it is and not fall down, I want to pick this out by hand so I can have a good look at it along with the rest of it as I take the level down.

Any way as I was drilling the shot holes my knee started to play up pretty bad, the left one that I had some cartilage out a few years back and has never been the same since, so after I had drilled the 3rd hole I decided to pack it in and go home, so I took 4 photos and quit, tomorrow is another day, the opal if there is any will still be there.

This is after the shot, the level still fell down for the most part and part of the roof as well as you can see here, the alanite above was sitting below some gypsum and had let go from it, better this way than when I am underneath it, although this is the soft stuff it still weighs quite a bit in a lump like this, you can also see it pulled some of the roof down where I have drilled, ready to blow it down just before I go home.

This is taken from the bottom of the shot and looking up to the back of it.

This shows you how I pull some if not all of the top of the dump down to make it flat on top so I can sit or lie down and pick the level or pick through the dump where the level has been brought down, I only check the dump at this time if I see some material or opal still in the wall or the level that is still where it should be, at this point there is some small trace of potch in the level.

But a small pocket of potch (just my luck) did turn up in the level, 2 photos down, that is the trouble with this game, we have no idea where the opal is or when it may came in the level as in this case one second there is no trace at all and then with the next pick there is potch 1/4 inch thick and then it is gone as quick as it came with no trace behind it.

You really have to look at this, as this is a photo taken upside down so to speak, I lay on my back and took a photo of the underneath of the gypsum in the roof where the Alinite had been joined on too, as you can see on the right side at the bottom near the fuse that it is smooth and on the left is very rough and pitted, marvelous how things form underground, we don't get mush chance to see things like this as we just blow it down, you can also see how some of the roof has gone leaving the fuses exposed, the one on the right in normal but the 2 on the left were hanging out, no problem here as I just roll them up and stuff them back into the holes and will light them when I am ready to leave, it will blow down the rest.

Went to see my Mate George the driller, he also classes opal and having a tunnel machine, remember the one that I showed you being put downunder, that was him and his machine, he finds opal on a more regular basis than me and as he has been doing this for over thirty years, he has a lot of experience in this area, I don't, you may think that I am doing well at the moment and you would be right, but this is not the norm, I go a long time with out even finding potch right now I am just on a good patch, but it will not last forever.

Anyway I will be going over to his house this Sunday Afternoon to have him class some of the latest bits and pieces I have found in the last couple of shots, below is what I was talking about earlier in the story about the shot face.

Well this is it, as I am pulling the shot and get past all of the loose dirt that I have thrown down when picking the top of the dump and the level and from blowing down the roof, we get to the shot proper, this is when we can see the ironstone level in the face of the dump, this is when I have to pay attention to the level.

I normally switch off the hand light and pull the shot face down with the blacklight on and the hand pick, this way everything that is potch or opal shows up white and easy to see, but if there is material in the dump and there was a bit in here from that vertical then it takes a lot longer to get the dirt out and I waste a few liters of diesel with the blower as it is idling while I am checking, I cannot stop the blower, I could, but I cannot start it from underground again so it is impractical to stop it for the short time I am checking.

As I only pulled 3/4 of the shot yesterday, I went in and finished the job this morning and by the time I had finished and checked the level with a bit of hand picking here and there as I always do, then I make sure the roof is safe and wall is clean and ready for drilling than pull back the dirt by hand that I have created, as the blower is switched off at this stage.

As it was just after 11am I figured that by the time I drill the holes and make the bombs it would be around 12 or 12.15, by the time I let the shot off it would be around 12.30 and seeing as there is trace in the level, so there is a good chance there will be something in the shot, I would need around 3 hours to check it out, so I decided to leave the shot until Monday morning.

Drilled the shot of 15 holes and then made the bombs, but this time I used some old fuses that have been made up for the past 4 years and sitting in the cutting room, I also had a new full roll of this fuse as well and I have already used this, in the beginning with no problems, but I had forgot that with this fuse you have to open the cut end with your fingernail or it is hard to light.

These fuses are 3 foot long and as I can now stay underground when I fire, this is what I need in length, this gives me about 1 and a 1/2 minutes and as I am only lighting 12 bombs it takes about 30 seconds to light them all, plenty of time to go around the corner and stick the fingers in the ear for when they go off.

What happened here was as I lit the first one, it seemed not to want to light so I went to get the wire cutters that I keep underground to trim the end of the fuses off before I light them in case they have dust or dirt in the end, (in this case it did not do any good) anyway as I got back to the shot the fuse was burning away, so I quickly went around the corner and waited for the bomb to go off, then I pulled the fumes from that so I could have a look at the results and then I had to clean up the dirt that was the result of the one bomb, below is the photo of the opening bomb.

You can see what it does in damp ground, the hole you see here is about 2 foot deep and as I drill this hole 3 foot deep as the opener, so 1 foot of the wall has come off, as you can see on the right hand side where the second bomb is, the wall is smooth and so it has let go, that bomb was hanging out of the hole and the next one on the end was also nearly out of the hole as the face had dragged them out as it fell off.

Changed some 6 fuses over but could not get them all out as the ground had squeezed the 2 center holes in and so could not get the bombs out and 3 more were stuck in also so had to light the shot with two different types of fuses which is not good, but as I had already done the top one I could not change them again, the fuses burn at different rates, the orange fuse is the old fuse and burns a bit longer per foot that the brown fuse.

I lit the shot and went down the old 25 foot drive and stuck my fingers in my ears, after the bombs had gone off I pulled the fumes and cleaned up a bit around the elbow, then I spent the next hour or so checking the level, this time it had not fallen down and so I had to jackpick it, but it was empty, not a bit of trace in there at all, so as I was going towards the old claim and going away from the slide I have called it quits on this drive and will start a new one tomorrow, No 3 drive.

You can see I am starting to get a bit of a dump going and why I put the blower over the side of the hill, this way I can get a lot more dirt up before I will have to ether push the dump over or move the blower when I get another shaft drilled, this new drive should go forty or fifty feet, then I will start another by then I will know where to drill the next shaft or two shafts ready for me to move the blower on to one of them.

This is the way I will be going with the next drive, I will have to blow some of the roof down to get some head room and also to give me a bit more head room at the bottom of the shaft I go down, I had a bit of trouble getting a ten foot pipe down the other day, so I will make the roof a bit higher, I will have to come up top again when I fire the shot and with the next one as well, until I am 3 shots in or 12 feet, I am 5 feet in from the shaft that has the pipes down it, so two more shots will do it.

Then after I have pulled the fumes, I can go down lower the telescope again as I will have to pull it up level with the roof or it will get hit by flying rocks etc and get damaged, then put the elbow back on and clean up with the blower then I will be able to drill a shot and fire it, dont know if I can get all of that done tomorrow but will try.

You can see that I use an little 12 volt air pump to pressurize the 44 gallon drum to push the diesel out through the plastic pipe that I use as a fuel hose, this works quite well, takes about 9 minutes to pump 100 liters and save me having to do it by hand and the pump to do it by hand costs well over $200 dollars, this tube that I put in through the drums cap cost me $5.00 to make, I used to do this when I was a roo shooter from 68 to 70 to put petrol in the ute and I can be doing other things while this is happening, like taking photos or putting the gear away.

Took a Tourist out with me today, he is one of our Newsletters Subscribers like you, name of Sean, nice guy was quite a thrill for him to come underground and he went down on the winch with no bother at all, so he has a bit of guts as it is scary the first time or so when you sit on the seat and have nothing under you but 80 feet of nothing.

All I did was to blow the roof down and some of the roof near the shaft I go down as I need more head room for putting pipes down, of course after I have drilled and made the bombs and Sean has seen what has gone on so far I have to bring him up, so I have to come up first and then send the seat down for him, I have a another switch up top that I use in situations like this as the person who uses the winch and seat must be in control of themselves at all times for safety reasons.

After Sean has come up, I then go down and light the bombs then come up and after they have gone off, pull the fumes with the blower, then I can go down and inspect the shot and check the roof for stability and if I feel that any of it looks unstable I take it down with the hand pick as I did in the shot, then I go up top and let Sean go down, then I bring the seat back up and I go down.

As I was dropping some of the roof with the pick and I discovered a bit of skin shell in the roof with a little bit of green color in it, when I checked the roof with the black light there was quite a few of then scattered around in the roof, nothing to get excited about I'm afraid, but did give Sean a bit of a thrill, there was other bits of potch in the roof in different places but did not lead to anything, but proves that there is another level just above me as shells and skin shells are always under a level, at least 1 to 2 feet down.

By the time I had checked here and there and had a bit of a pick in the pocket that I found potch and some green color in for him to see if I could find a bit of opal for him to see, which I did, I found a bit of green blue in there and then I left it alone as I will put a couple of shots under it later on and save myself some hard work in jackpicking.

Went to pull the roof shot and by the time I had set up the telescope and elbow and messed around pulling the dirt and some of the damp ground that is still left, is a lot of messing around and hard work cleaning up beneath the shafts after a shot and takes time, so after 1.75 hours of hard work I decided to leave the rest which is about half, until tomorrow, so I came up a checked on top as to which way I was going to make the drive.

To my surprise I had the direction wrong underground, just as well I checked up top before I drilled and fired the next shot, I had forgot that the main slide runs along at an angle to the shafts I had drilled, so the direction that I showed you in the photo above is wrong, I will take another photo tomorrow but before I put the truck in position to go down, I have marked the slides track with rocks so I know which way it goes and I have also marked the spot which I must drive to.

Now I have to blow the rest of the roof down, I had left a corner of the roof and the last of the damp ground to be taken out when I was going to start another drive later on, but now it is my way and will have to be dealt with tomorrow, so again I have to mess around with the cleaning up and I will have all this mess again for the next two shots at least, the first one blows the dirt out just about right under the shaft and the second shot will do the same but not quite as bad.

Below is the section of the roof that has to be blown down, its like a knob just hanging there, so I will put 2 bombs in it and blow it down, then the roof should be same height as the rest and be safe to work under.

This is where I have just blown down the roof and taken some of the damp dirt out, you can see the nice ironstone level here but there is no trace at all showing, you can also notice how dark the sandstone is here, that is because it is damp or wet as I call it, I think I will put a shot here before I start the new drive as that blue green trace is right next door so all I have to do is put 3 bombs under the level and let then blow sideways so I can pick the level down and see if it makes a pocket in there.

After I have drilled the roof, made and loaded the bombs, I had to come up and disconnect the top elbow and pull the pipes up a few feet to get the telescope away from the blast so it doesn't get damaged, also pull the operating leads up as well and just wrap them around the winch handle, then I go down and light the bombs then come up and when they have gone off, I lower the pipes again, start the blower and reconnect the elbow put the clamp on and pull the fumes for a couple of minutes, then go down and check.

Here I have pulled about half of the dirt and I will finish the rest tomorrow and get ready for the next shot, you will notice that I always have the electric jackpick there, I could not work without this as there are a lot of big pieces and some small but have or are full of gypsum and are very hard to break with the hand pick and also take to much energy out of me so its the electric jackpick, bit disappointed this week as I have only done one shot, but all this I have done was necessary in making things safe for me to work and for starting new drives in the future, now will start the prospecting as we call it or you might say looking for opal, whatever its going to be a costly job unless we get lucky real quick.

I finished pulling the dirt and all of the wet dirt that was left in that corner and it was very wet at the bottom, gave me a blockage about 10 minutes before I was finished, had to go up and unblock the top elbow, then go down and finish the job, now I am ready to drill a shot on Monday, the direction that I showed you in the photo above is wrong for the new drive, but I will put the next shot there to have a look at the level, then if there is nothing there I will the dirt there and only pull enough to clean up for the next shot.

This is a shot to where I am heading for with Drive No 3, looking back at the blower and shafts, the little pile of rocks is the direction I will be heading for, the drive will go past this spot I should think, but like everything I am not 100% sure at this time, but in theory if I am correct I should strike material about 10 feet back from this spot.

This is a view from the shafts looking out to the virgin ground, now I have two major drives to do to see if there is anything around, this one in this direction which will go as far as I can pull dirt in the wet ground, about 60 or 70 feet and if I find any material or opal then I will know where to look and will drill a couple more shafts and the next drive will be to the left as you are looking here, in-between the two faults or small slides where I have just found the opal and material here, which was right in the middle but about 22 feet out from the major slide which is on the right of the picture.

As I said before it is now back to prospecting, when I start drive No3 it will be a bit narrower that what I have been doing until I cut some material than I will go wider, so after the next shot which I am only having a look at the level and some trace, I will be only going 3 bombs wide at the top, which will make it quicker to drill and pull the dirt not to mention cheaper as well.

Keep Tuned as I will have another shot or 2 to talk about next week and well who knows what we might find.....

Again I Hope you have enjoyed this issue and look forward to the next one, hopefully I will have some more good photos to show you in the next issue and maybe some of Good Looking Opal and lots of it, I am still hoping that this will be a good year for us in mining, so stay with us over the next few months and find out what goes on in our part of the world as far as Opal Mining goes.

Until the next issue.........

and wish me lots of LUCK.

Cya Later, Stuart Bird.

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