steve62 got a reaction from Ronald C in Sampling Methods For New Placer Mine
Carter / Ronald,
Lot's of variables here so I can only speak about what I am doing.
I have a Track-Mounted Hydraulic Auger. Drilling 9 inch Holes down to as much as 20ft. 20ft., right or wrong, is my Cut-Off in terms of how much Frozen Overburden I would be prepared to shift to get at Pay. If I'm not in Pay by 20ft. and the ground is not changing much then I'm out and moving. For example, I have just moved to a new area where a 1907 USGS Bulletin states that Bedrock was reached in a Shaft @ 97ft. The top 40ft. is Gravel but if I haven't hit Pay by 20ft. then I'll move. All the ground is Frozen. If I'm in Pay @ 20ft. I'll keep Drilling.
No need for Casing. Lot's of extra work. Frozen Ground holds up really well apart from the expected Thawing around the collar. Thawed ground is also quite stable. This could vary greatly depending of course on what and where you are Drilling. A Gravel Bar in the River would be problematic for example and apart from the Hole caving, I would expect there would be water ingress at some depth. This tends to wash Sample off the Auger flights.
As far as the accuracy of an Auger, I haven't had any problems and in fact, Sample results can be remarkably accurate and consistent. One way I realised this quite quickly is when I wanted to do some Sample checking so I Drilled a series of Holes on close spacing then Logged the results and found them to be all very similar. I.e. Similar amount of Gold at the same depth sitting on a Clay layer. Barren Gravels still barren. 2ft. Of Clay above Bedrock. Zero colour on Bedrock etc. etc. The talk about Dilution or having additional Sample or even Gold drop off the Flights and fall down the Hole to a deeper layer is not necessarily nonsense but is not a major problem and with your own experience you will soon get to notice anything unusual or out of place in your Samples.
If you are Drilling Gravel you will naturally come across all the various materials such as sand, silt, fine gravel, pebbles, cobbles, greenstone, limestone, quartz, etc. etc. and usually with various amounts of Clay intermixed. We Drill through everything including cobbles up to 8" diameter or larger. I don't know if I have been through much larger than that or not as the larger rock gets ground up in to chunks so maybe I've just been lucky but I do know that the right type of Auger, i.e. Bullet-Tooth which is an aggressive bit configuration, will wear away and break up large Gravel to a certain limit. You will have to sit on it for several minutes grinding away and slowly increase the down-ward pressure until the rock starts to break up but it is do-able and is better than having to abandon a Hole then move and start a new one. These things will get easier with practice. Every Hole presents different challenges. The worst of which for me is Frozen Clay. Sometimes 10 to 12 Ft. of it.
Each Machine will also have it's own limitations and ground conditions will vary widely but it ( Auger Drilling ) can be a very useful way to get a good look at what is below the surface and in my own experience appears to be quite representative although Bulk Sampling of larger volumes will still be required if a Block of Pay can be outlined with the Drilling.
Good luck with it and I for one would be very interested to hear about your experiences.
steve62 got a reaction from Geowizard in Residual Magnetic Intensity
You have my attention yet again. Very interesting topic and I probably should read Chris' Article before posting this but I just wanted to provide an example of the dilemma that most of us humble Prospectors face and for me at least, it can be summarized in a single word - INTERPRETATION.
For my area where I work I have just about everything that I could find which was available from the USGS and includes, but is not limited to, all of the following Maps / Surveys / Reports etc. etc. -
1. USGS Bulletins.
2. MinFile & Open File Reports.
3. Survey - Total Magnetic Field and Detailed ElectroMagnetic Anomolies - In Black & White showing Gamma Contours.
4. Survey - Total Magnetic Field - In Color, no Contours.
5. Survey - Aeromagnetic. ( Yes, different to 3 & 4 above )
6. Survey - 7200 Coplanar Resistivity.
7. Geology of the Quadrangle.
8. Topography of the Quadrangle.
And believe it or not, there were more Geophysical Surveys which I haven't had time to get to just yet so a special thanks should go out to the USGS for such a comprehensive effort. I wonder if they wouldn't mind dropping by my Claims next Summer to Interpret all the Data for me ?
Getting back to the problem - INTERPRETATION. Obviously, I need to further educate myself in order to understand what on earth I am looking at. Enlisting the help of a Geologist seems to be the only option however, if you have some advice for us which is relatively easy to understand then we are all ears. Any and all suggestions are always most welcome as the Gold seems to have it's own way of staying hidden despite our best combined efforts.
Btw, I trust your Summer was a productive one up at Ophir.
steve62 got a reaction from gmeyer in "flour Gold" Recovery
Setting aside the Chemical Technicalities for a moment, isn't this supposedly a Placer Deposit ? And how many people generally use Fire Assay to sample a Placer Deposit ? In fact, hasn't it been said by many an experienced Geologist NOT to rely on Fire Assay to sample Placer Gold ? In which case, why not just run it through a WashPlant and get as much as possible ? If there is concern that you are losing significant amounts of fine or flour Gold, then run the Sluice Cons through a Concentrator as suggested by Robert above - either a Knelson or an Icon. If you decide to go to the trouble / expense of setting up a more Technical " Circuit " and can get control of your Water through a Re-Circulating System, Floculants can be added to the water itself which apparently encourages the " Floating " Gold to sink and subsequently be captured / recovered.
Any of these non-standard Recovery methods require a lot of testing to achieve the ideal balance of Chemical vs Metal to reach the desired result of recovering more Gold. There would have to be a significant amount of Gold being lost in those Tails though to justify setting up anything more complicated than a standard Gravity system, particularly if it involves Chemical extraction. I don't think any of us ever expect to recover much more than 90 + % anyway.
Flint - If it's an extensive Deposit that justifies the expense and your friend has been unable to come up with any method of recovery, then it looks like he has no choice other than to do some serious Bulk Sampling through a purpose-built Pilot Plant under the guidance of a good Metallurgist. Best of luck with it and let us know the outcome in the event one of us experiences a similar problem.
steve62 got a reaction from Ronald C in Ice Cold Gold!
Reality Miners ? It reminds me of one night early September I was coming back in to Town ( Nome ) to get some Fuel / Supplies. I had been riding the ATV hard all afternoon in the rain coming out of the bush. I got to my Truck out at the main road then headed back towards Town. By this time it's nearly 1:00 am. I was cold and hungry, hadn't showered for days and just as I was about to stop and heat up a packet of two-minute Noodles, I came up to the Safety Roadhouse. ( 20 Miles out of Nome )
Lo and behold the lights are still on, courtesy of the " Reality Miners ". There was a party on. I walked in and the place was full of the Discovery crowd. Bloody Mary's flowing freely, Cheeseburgers all round and the Fire was burning in the corner. I must admit, I sort of wanted to find out more about the " behind-the-scenes " workings of the whole affair and if there was anything different to look forward to this Season but I was just too tired to bother listening to the BS of how hard they were doing it. I could see how hard they were doing it. I sat quietly alone near the Fire warming up and stuffed in two Cheeseburgers so fast I didn't even taste them. No-body really wanted to know what the hell I was up to at 1:00 am in the middle of nowhere. I think it must have been how I looked or probably how I smelt, not to mention my somewhat primitive table-manners. The proverbial Caveman was in the room. Come to think of it, Prospecting alone wouldn't make for enough Drama for TV. They need the conflict and tension between egos which usually arises out of the stress and tiredness of working long hours. And the worse things are going, the higher the levels of stress and conflict.
I can't really complain though. I watch all of it for every small idea I can come across. I must say though that after watching Gold Rush now for several Seasons, I see in the latest Episode this weekend that the Hoffman Crew have just run dirt for two weeks in Guyana and didn't turn up a single flake. Wow ! I used to think that inadequate Sampling was a Rookie mistake or a simple lack of patience so I more or less forgave them over the first two Seasons but here we are, several Seasons later and now these guys are not Rookies any more. They have experience, an apparently unlimited Budget ( courtesy of Discovery Channel ), more Machinery than they know what to do with courtesy of Volvo and yet still, despite the efforts of Freddie Dodge to make Gold appear in every Pan, the Hoffmans still don't seem to want to Sample their ground properly. For all their fancy Equipment, Consultants, Egos, Witch-Doctors and Diviners, if there's no Gold there, don't even bother. If I had to offer up a simple piece of advice for these guys, it would be to just get back to basics. Were getting tired of the same stupidity over and over.
steve62 got a reaction from Geowizard in Ophir Placer Gold Mine - An Example
Geo - Ref. Post #45.
I note that you seem to have a preference for Doosan Loaders. I think the discussion about Equipment is very important. Just as a matter of interest, I recently had to renew my Wheeled Loader Ticket ( FEL ) and the chosen Machine in use by the Registered Training Company was a new DL250. Very nice Machine to operate.
I am currently on a Construction Job and one of our main Loaders is a Doosan DL300. This thing is fast and responsive. Bucket capacity is about 3.5 CuYds. We also have a Doosan Excavator on Site. Generally speaking, there seems to be a wide-ranging acceptance of Doosan Equipment on several Jobs I have seen since getting back from Alaska. Notwithstanding the fact that they are of course cheaper than Cat or Komatsu, we still have to consider how we are going to get parts when working in remote areas. Do you know by any chance if Doosan have an Agent / Distributor in Anchorage ?
Speaking of Bobcats, we have a wheeled ( Rubber Tires ) Bobcat on Site as well as a Rubber-Tracked Machine. ( Posi-Track ) Interesting to compare the pros and cons of both types of Machines. Seems to me though that the Posi-Track has the upper hand. Goes anywhere and fast. It's a Cat 277B. I happened to be talking to the Posi-Track Operator this morning and he suggested that if he had to spend say $160,000.00 on a 4000 Hour Cat 330DL for example, he would rather have 2 x low-hour DX300's ( Doosan Excavators ) for the same price, rotating each one in and out of service on a week-on / week-off basis. Problem of course would be double Freight on two Machines but imagine the availability ?
Just one thing to consider when working in Alaska with these newer Model Machines - lots of Electronics.
steve62 got a reaction from Geowizard in Mining Based Reality Tv Shows
The Mining reality shows are about to start again next week. Season 4 of Gold Rush has the Hoffmans in the jungle in Guyana this Season while young Parker is now up in the Yukon under the guidance of Tony Beets and trying to start his Mine with 100 Oz. of Gold. Dakota Fred is still in Alaska so we'll have to see what he gets up to. Should be interesting and I am particularly keen to see how the Hoffmans mobilize their usual over-sized gear and crew without the benefit of a road.
Jungle Gold, filmed in Ghana, has already shown Season 2 and ended with the entire Film Crew having to leave the Country. Simple reason - Local Law doesn't allow Small Scale Mining for Foreigners. Larger Mining Investment is of course welcomed in most Countries, including Ghana, but the 25 Acre Small Scale Concessions ( Claims ) they were working are reserved for Ghanaian Nationals only. They should have known this even before they got off the Plane.
Season 2 of Yukon Gold has started showing in Canada but I haven't been able to watch any Episodes as yet. This is a fairly good Show and is well worth watching if you can find a decent Link.
Bering Sea Gold has Filmed another Season and that usually starts showing on TV later in the year. I saw them when I was in Nome and this year sees a couple of new Crews. Should be worth the effort to watch. Keep an eye out for some new " Talent ".
Another new Show yet again this Season - It's called Alaska Gold Diggers. It's on Animal Planet. Not sure if Ice Cold Gold got dropped but as Chris mentions above, it seems like all the big Cable Channels have to have a Mining show. This one has 5 Women. Looks like they try their hand at Dredging so that in itself should make for a good laugh or two.
So there's at least 4 x Shows coming up over the next few months.
steve62 got a reaction from Geowizard in Fortescue Metals Group (Fmg)
Yes, they have done very well in a short period of time. Absolutely nailed the timing of the Iron Ore ( Commodities ) Boom over the past few years. It's all about China Inc. Even though the bulk of their Steel Mills might be running at a loss, they continue to build their Ghost Cities and churn out Steel at record levels.
As you probably know, Fmg doesn't ship from Perth, they ship from Port Hedland. PH is closer to China than Alaska. The quality of the ( Iron ) Ore they Ship is fairly good. The DSO ( Direct Shipping Ore ) is generally around 62 % = Hematite. The Magnetite ( 20 % to 40 % Iron ) Mines are concentrating to about 60 % to 67 % and that is an expensive exercise. The North West of Western Australia has an advantage over Brazil mainly in Freight costs so they can land Ore in China at a cheaper rate than Vale ( Largest Brazilian Miner ).
Any Iron Ore deposit in Alaska would have to be reasonably close to a Port. Fmg, Rio Tinto and BHP have all built their own Railways to Port. These are Multi-Billion Dollar Projects moving Hundreds of Millions of Tonnes of Ore. Imagine Pebble x 3 or 4 in scope and then try and imagine the nightmare of Permitting even just the Railway, let alone an expansion and dredging of the Port to take the Bulk Carriers. Of course, any potential Iron Ore Mining in Alaska doesn't have to be on a massive scale to make money. It might be feasible if the grade was good ( + 60 % Iron ) and the infrastructure was possible but any Deposits which are isolated too far inland are more than likely to remain exactly where they are.
steve62 got a reaction from Geowizard in Who Got All The Gold ?
It must be just about time to Report in for those working further North. So how did you all go ? We are all interested in hearing some Summer stories. Nobody of course want's to give up too much info. but I'll start off by saying that I had a really tough Summer. I got some color where I thought I wouldn't get anything and I got nothing where I thought I would definitely get something. Just goes to show that the Gold doesn't always like to co-operate, no matter how much we think we know about it.
The usual challenges were there. Lot's of rain, muddy Trails and luckily only one Bear that disappeared quicker than I could draw the peacemaker. High water in the Rivers, digging through 6ft. of Clay, getting bogged etc. was all part of the fun. Roll on next Season.
steve62 got a reaction from Geowizard in True Cost To Mine Gold - Companies Under Pressure
Hidden Valley Mine for example in Papua New Guinea reported Production Costs of $1,790.00 / Ounce last quarter and Logistics aren't that bad as there has been a number of large Mining Operations there for well over 20 + years. Another in the Solomon Islands @ $1,663.00 / Ounce. There is a lot of talk already stemming from last week's price plunge that Exploration Budgets are getting the chop big time.
Other more expensive methods of Mining, particularly Mechanised Underground Mining, will also come under scrutiny as Companies try and cut costs. The other thing we are also seeing now is the Sale of some of the marginal Mines. Barrick are selling 3 of their Mines in Western Australia for those of you with some spare Cash.
Costs are so far out of control that it is bordering on the ridiculous. Barge Freight is up again this Season. Labour is worse. I saw an advertisement in the paper recently from somebody who said he can fix Hydraulics. I thought the Service might some day be useful. He quoted me almost $1,000.00 / Day + Meals + Hotel + Airfares + Transportation + Satellite Communications / Internet + Private Sleeping & Bathroom arrangements etc. etc. I wrote back and asked him, in addition to his list, did he have any special Dietary or Bedding requirements ? For example, did he like his Quail Roasted or Poached ? And the Pillow, was that Super-Soft Down Fill or would standard 100 Micron Duck Feathers be O.K. ? Reminds me of a time when the Union called a Strike to shut down the entire Mine because the Pie Warmer wasn't working and so no-body could Toast their Sandwiches.
The problem we have as small Ma & Pa Operations is that the big, Publicly-Listed Multi-Nationals with deep pockets have no problem paying whatever it takes so the Supply / Demand equation is leaning way too heavily towards too much demand which of course equals rising costs. If and when that starts to balance itself out again, perhaps we might then start to see some of the cost and labour pressures stabilise a bit and hopefully come down to a more realistic level. Until then it looks like we have just to grin and bear it or get the Kids more involved.
steve62 got a reaction from Cochetopa in Ice Cold Gold!
Geo - I know you've been there so you must have felt right at home. How do you land a C-130 in fog like that ? With great difficulty and a quiet prayer I would imagine. Yes, nice scenery with an Iceberg or two thrown in for effect. Weather seems pretty much like Nome. And Logistics ? Wow ! Could you imagine getting an Excavator or a D-9 in there ? Perhaps I haven't seen enough of the place yet but I am already wondering what the Placer Miner is doing there ? And enlighten me if you can please but what does an Excavation Expert actually do ?
Be interesting to see how it pans ( excuse the pun ) out. At least these guys have started from scratch. i.e. It looks like they are going to show us some real Grass-Roots Exploration / Prospecting and in addition, lo and behold, no it can't be - A Geologist ! Could this be the first Mining Reality TV Show that actually thought it might be useful to bring in a Geologist ? Surely not ! It would have got even better if the Geologist had briefly explained in laymans terms how and why he has selected those 3 Targets near the Base Camp. Heck, we may have even learnt something !