- To participate in the 911Metallurgist Forums, be sure to JOIN & LOGIN
- Use Add New Topic to ask a New Question/Discussion about Geology and Geometallurgy.
- OR Select a Topic that Interests you.
- Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
Using Add Reply allows you to Attach Images or PDF files and provide a more complete input. - Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.
4
REPLIES
862
VIEWS
Started by rios
I am starting a new gold mining project in Zimbabwe. I have contacted a Geologist and Geophysicist who did a Magnetic Survey on the target area. He also did a Resistivity and I.P. Survey. No other method was used and one has to dig 8 meters into muds...
I am starting a new gold mining project in Zimbabwe. I have contacted a Geologist and Geophysicist who did a Magnetic Survey on the target area. He also did a Resistivity and I.P. Survey. No other method was used and one has to dig 8 meters into muds...
3
REPLIES
729
VIEWS
Started by Bluegene66
Combination of high grade Zinc/Gold in a VMS system is very rare ie: 5m of 12% Zinc 14g/t Gold 1%Cu in a core sample. Can someone explain the structure and the significance of this unusual occurrence. Thanks.
Combination of high grade Zinc/Gold in a VMS system is very rare ie: 5m of 12% Zinc 14g/t Gold 1%Cu in a core sample. Can someone explain the structure and the significance of this unusual occurrence. Thanks.
Last commented on by
Do you have any gold or zinc in quantities you want to sell
Do you have any gold or zinc in quantities you want to sell
2
REPLIES
200
VIEWS
Started by aufinder
Trying to Identify Ore pics attached close up and angles I believe this ore to be Cavarite ...(Krennerite or Sylvanite or Combo? or least gold Telluride Calaverite? I have acid washed this Specimen once 2 weeks ago with muratic and it stayed ...
Trying to Identify Ore pics attached close up and angles I believe this ore to be Cavarite ...(Krennerite or Sylvanite or Combo? or least gold Telluride Calaverite? I have acid washed this Specimen once 2 weeks ago with muratic and it stayed ...
Last replied to by aufinder
Thanks I did a positive reaction with a small piece of the ore, and it was AU definately that it converted reacted into. I will have to extract the gold now, wow 66lbs at 40% gold is a lot of cash, ra...
Thanks I did a positive reaction with a small piece of the ore, and it was AU definately that it converted reacted into. I will have to extract the gold now, wow 66lbs at 40% gold is a lot of cash, ra...
9
REPLIES
441
VIEWS
Started by montsep
I'm an environmental journalist and I'm preparing an article on photovoltaic cells. I would like to know the degree of exploitation of world quartz resources, and the current trend of this figure, given nowadays extraction rate. I'd like to know als...
I'm an environmental journalist and I'm preparing an article on photovoltaic cells. I would like to know the degree of exploitation of world quartz resources, and the current trend of this figure, given nowadays extraction rate. I'd like to know als...
Last replied to by Robert W Schafer
On a commercial scale metallurgical silicon metal is produced by the carbothermic reaction of silica (quartz) in an electric arc furnace using carbon electrodes where the temperature in the main react...
On a commercial scale metallurgical silicon metal is produced by the carbothermic reaction of silica (quartz) in an electric arc furnace using carbon electrodes where the temperature in the main react...
1
REPLY
505
VIEWS
Started by NGVirginia
I have access to a Copper-Molybdenum tailings site with the following mineral content present (grams/ton): Bismuth - Bi (0.9), Selenium - Se (0.7), Tellurium - Te (0.4), Rhenium - Re (0.15), Gold - Au (0.015), and Silver - Ag (0.5). I am having diffi...
I have access to a Copper-Molybdenum tailings site with the following mineral content present (grams/ton): Bismuth - Bi (0.9), Selenium - Se (0.7), Tellurium - Te (0.4), Rhenium - Re (0.15), Gold - Au (0.015), and Silver - Ag (0.5). I am having diffi...
Last replied to by Jorge
Do you know the cooper grade?
Do you know the cooper grade?
0
REPLIES
355
VIEWS
Started by banoda
I have started gold mining in Ethiopia and looking for advice and information relating gold wash machine up to 8 ton per hour, and am newly born in conducting gold mining and have lease for land to explore and extract gold sand. I need your advice t...
I have started gold mining in Ethiopia and looking for advice and information relating gold wash machine up to 8 ton per hour, and am newly born in conducting gold mining and have lease for land to explore and extract gold sand. I need your advice t...
2
REPLIES
535
VIEWS
Started by Nish
Hi guys, I've recently been given an opportunity to work on a geo metallurgy focused project, I however am a geologist and not very familiar with geo metallurgical processes. Could the metallurgists on here please advise on synthesis gold doped sy...
Hi guys, I've recently been given an opportunity to work on a geo metallurgy focused project, I however am a geologist and not very familiar with geo metallurgical processes. Could the metallurgists on here please advise on synthesis gold doped sy...
Last replied to by Todd H
Perhaps I dont fully understand - I dont think adding gold to pyrite is going to greatly enhance its flotability and certainly not going to enhance the project economics. Pyrite is one of the easie...
Perhaps I dont fully understand - I dont think adding gold to pyrite is going to greatly enhance its flotability and certainly not going to enhance the project economics. Pyrite is one of the easie...
2
REPLIES
658
VIEWS
Started by lkperumal
Dear all, I am searching about the magnetic properties of ferrosilicon ( 15% or 20% Si content). Anyone, please send me complete magnetic property details of FeSi with various composition. Thanks in advance
Dear all, I am searching about the magnetic properties of ferrosilicon ( 15% or 20% Si content). Anyone, please send me complete magnetic property details of FeSi with various composition. Thanks in advance
Last replied to by lkperumal
Thank you for your reply, Actually the question is about FeSi powder (in size range of microns). I have an idea to use this ferrosilicon powder to replace corbonyl iron powder in MR fluids. As it has...
Thank you for your reply, Actually the question is about FeSi powder (in size range of microns). I have an idea to use this ferrosilicon powder to replace corbonyl iron powder in MR fluids. As it has...
0
REPLIES
472
VIEWS
Started by oluwatunmise
Hi everyone, Have been given an opportunity to talk on different approaches to gold exploration in basement terrain (i.e Geochemical, Geophysical, Geological, Mineralogical, etc). However, am a geologist but not well inclined to this approaches. plea...
Hi everyone, Have been given an opportunity to talk on different approaches to gold exploration in basement terrain (i.e Geochemical, Geophysical, Geological, Mineralogical, etc). However, am a geologist but not well inclined to this approaches. plea...
2
REPLIES
547
VIEWS
Started by Mattiel
Hello Everyone, we have recently acquired a claim with an old mine on it. We took some grab samples from inside the mine. We took samples from both the vein, and altered wall rock. We have done roughly 5 sets of testing with an average grade of ~15g/...
Hello Everyone, we have recently acquired a claim with an old mine on it. We took some grab samples from inside the mine. We took samples from both the vein, and altered wall rock. We have done roughly 5 sets of testing with an average grade of ~15g/...
Last commented on by Jackievs
Apologies I was directing my question to Hamid...
Apologies I was directing my question to Hamid...
1
REPLY
564
VIEWS
Started by PJ
I work in a very heterogeneous, nuggety narrow vein gold deposit, and I am looking for a way to catch jumbo or longhole cuttings as a slurry before they land on the sill and become contaminated, and the gold separates. Has anyone here solved this iss...
I work in a very heterogeneous, nuggety narrow vein gold deposit, and I am looking for a way to catch jumbo or longhole cuttings as a slurry before they land on the sill and become contaminated, and the gold separates. Has anyone here solved this iss...
Last replied to by Sylvain Tremblay
The solution would be very quick if your production drill was an In the Hole drill rig as you would be able to transform it, without a great investment into an RC drill rig and therefore catch your dr...
The solution would be very quick if your production drill was an In the Hole drill rig as you would be able to transform it, without a great investment into an RC drill rig and therefore catch your dr...
5
REPLIES
3288
VIEWS
Started by Charlie
Hello guys, does anybody know what variables are needed/ taken into account to establish an optimum ratio for ore blending? I'm blending two different Pb-Zn ROM samples (low and high grade).
Hello guys, does anybody know what variables are needed/ taken into account to establish an optimum ratio for ore blending? I'm blending two different Pb-Zn ROM samples (low and high grade).
Last replied to by OberstGruppen
About ore blending & stockpiles: Since the function of the stockpile is to act as an ore reservoir rather than as an ore processor, the action of forming a stockpile should have as little effect as ...
About ore blending & stockpiles: Since the function of the stockpile is to act as an ore reservoir rather than as an ore processor, the action of forming a stockpile should have as little effect as ...
3
REPLIES
478
VIEWS
Started by louwrens
Hi all we have a mining operation, and our lab cannot explain the fire assay results provided, we did quite extensive test work on the ore and have received inconsistent results. Once the ore is delivered to our site the ore tests at 40-60 g AU per ...
Hi all we have a mining operation, and our lab cannot explain the fire assay results provided, we did quite extensive test work on the ore and have received inconsistent results. Once the ore is delivered to our site the ore tests at 40-60 g AU per ...
Last replied to by Siddiquf
Representative sampling of broken ore is always problematical. Inconsistency in your case may simply be due to the sampler picking up the well mineralized pieces selectively in the first sampling.
Representative sampling of broken ore is always problematical. Inconsistency in your case may simply be due to the sampler picking up the well mineralized pieces selectively in the first sampling.
1
REPLY
577
VIEWS
Started by Moneer_Noor
we have several quality issues at magnesite mine (ultramafic alteratoin type). we are sampling 1 sample from blasthole material which depth in 4 meter for each hole to grade conrolling ROM. several quality issue is recorded. the mine material qualit...
we have several quality issues at magnesite mine (ultramafic alteratoin type). we are sampling 1 sample from blasthole material which depth in 4 meter for each hole to grade conrolling ROM. several quality issue is recorded. the mine material qualit...
Last replied to by Marshal Meru
I think it is also important to know the location of the sample. Blast hole sampling is the only one that gives you the location information. So I will keep this one for sure. I will try to reconcile ...
I think it is also important to know the location of the sample. Blast hole sampling is the only one that gives you the location information. So I will keep this one for sure. I will try to reconcile ...
3
REPLIES
2198
VIEWS
Started by oro
Modern geophysical methods of mineral exploration are still too expensive for many small commercial scale placer miners, and seem to require a high level of learning and deployment. I sometimes think / dream about a simple device that would measure...
Modern geophysical methods of mineral exploration are still too expensive for many small commercial scale placer miners, and seem to require a high level of learning and deployment. I sometimes think / dream about a simple device that would measure...
Last replied to by oro
Thank you Rockdoc and Don for your responses. Basically I would like to buy a simple device (geophysical, not drill) to keep on hand, for simple estimates of depth to bedrock. I see simple devices f...
Thank you Rockdoc and Don for your responses. Basically I would like to buy a simple device (geophysical, not drill) to keep on hand, for simple estimates of depth to bedrock. I see simple devices f...
1
REPLY
575
VIEWS
Started by Happiness
I need a scenarion where gravity method is deployed for inverstigating an ore body in contrast to the surrounding
I need a scenarion where gravity method is deployed for inverstigating an ore body in contrast to the surrounding
Last replied to by BAUD
Gravity separation is a concentration separation process in which minerals are separated from each other based on the difference of their specific gravity in a fluid medium. The applicability of grav...
Gravity separation is a concentration separation process in which minerals are separated from each other based on the difference of their specific gravity in a fluid medium. The applicability of grav...
1
REPLY
632
VIEWS
Started by Witzcat
Dear experts, I would like to summarize all metals used for producing a car by calculating the mineral raw materials needed for each metal contained in a car. Of course I understand that each location and lagerstatte is different and there is not re...
Dear experts, I would like to summarize all metals used for producing a car by calculating the mineral raw materials needed for each metal contained in a car. Of course I understand that each location and lagerstatte is different and there is not re...
Last replied to by David
This is a tough one. I did something similar just for the iPhone 6. https://www.usgs.gov/ was useful. I never did find what you are looking for exactly. I had to do math and plugin basic assumptions....
This is a tough one. I did something similar just for the iPhone 6. https://www.usgs.gov/ was useful. I never did find what you are looking for exactly. I had to do math and plugin basic assumptions....
3
REPLIES
924
VIEWS
Started by Nugget-hunter
identification of nugget of native metal found on the edge of granite country in northern Queensland Australia. SG of 5.4 and does not attract a magnet.
identification of nugget of native metal found on the edge of granite country in northern Queensland Australia. SG of 5.4 and does not attract a magnet.
Last replied to by Terrance
Process for extraction of platinum group metals from chromite-bearing ore US 4295881 A ABSTRACT A process for treating chromite-bearing ores to obtain useful mineral values, especially platinum ...
Process for extraction of platinum group metals from chromite-bearing ore US 4295881 A ABSTRACT A process for treating chromite-bearing ores to obtain useful mineral values, especially platinum ...
2
REPLIES
660
VIEWS
Started by jlpalacios
Hi, My name is José Luis, and I am doing my PhD about the assessment of mining/metallurgical processes by applying the Second Law of Thermodynamics. I am on the stage where I need to start to model a mining process. Would you mind telling me, w...
Hi, My name is José Luis, and I am doing my PhD about the assessment of mining/metallurgical processes by applying the Second Law of Thermodynamics. I am on the stage where I need to start to model a mining process. Would you mind telling me, w...
Last replied to by David
https://www.911metallurgist.com/blog/mineral-processing-extractive-metallurgy-methods https://www.911metallurgist.com/blog/mineral-processing-flowsheets
https://www.911metallurgist.com/blog/mineral-processing-extractive-metallurgy-methods https://www.911metallurgist.com/blog/mineral-processing-flowsheets
2
REPLIES
940
VIEWS
Started by Simon-Flotation
During a recent visit to a copper mine in Chile, plant metallurgists mentioned they got colloidal silica in their ore, and it cause some process problems. I guess it is non-crystalline silica or amorphous silica, it has the same chemical structure wi...
During a recent visit to a copper mine in Chile, plant metallurgists mentioned they got colloidal silica in their ore, and it cause some process problems. I guess it is non-crystalline silica or amorphous silica, it has the same chemical structure wi...
Last replied to by Robert
There seems ample evidence that amorphous materials are present to surprisingly high extent in orebodies as mined as well as being created by reactions during processing. This includes siliceous, oxid...
There seems ample evidence that amorphous materials are present to surprisingly high extent in orebodies as mined as well as being created by reactions during processing. This includes siliceous, oxid...
3
REPLIES
927
VIEWS
Started by Biglizer
Hello everyone I have some few questions to ask: I encounter an outcrop of quartz vein larger more than 5 feet wide,first assay of a sample shows about 0.4ppm,i decided to do trenching and pit sampling...few samples by sorting show few gold by pa...
Hello everyone I have some few questions to ask: I encounter an outcrop of quartz vein larger more than 5 feet wide,first assay of a sample shows about 0.4ppm,i decided to do trenching and pit sampling...few samples by sorting show few gold by pa...
Last replied to by mkdevarajan
There are many places where isolated small quartz veins may give high grade gold mineralization which may support artisanal gold mining. But they may be far placed from each other that commercial mini...
There are many places where isolated small quartz veins may give high grade gold mineralization which may support artisanal gold mining. But they may be far placed from each other that commercial mini...
6
REPLIES
1454
VIEWS
Started by Rahil Khan
It is common to find readily usable drill core sampling policies that many exploration sites use as part of their assay and prep labs procedures.Drill core being in many cases the only sample material available for early metallurgical testing.
It is common to find readily usable drill core sampling policies that many exploration sites use as part of their assay and prep labs procedures.Drill core being in many cases the only sample material available for early metallurgical testing.
Last replied to by Aminpro
At Aminpro Labs we do quite a few geomet studies per year. With help from geologists we first select ore domains by alteration and lithology and sometimes we take those and may divide them by low or...
At Aminpro Labs we do quite a few geomet studies per year. With help from geologists we first select ore domains by alteration and lithology and sometimes we take those and may divide them by low or...
4
REPLIES
2121
VIEWS
Started by Chifita
I recently came across such a mineralisation from an area with a lot of Hematite-Magnetite and just on the peripheral zones of the Lufilian Arc in Kasempa District of Zambia. I carried out a research which indicated that it was acicular malachite! ...
I recently came across such a mineralisation from an area with a lot of Hematite-Magnetite and just on the peripheral zones of the Lufilian Arc in Kasempa District of Zambia. I carried out a research which indicated that it was acicular malachite! ...
Last replied to by Mathias
Regarding the weird looking malachite, this mineral is readily soluble in weak acids. So it should reacht with hydrochloric acid. Did you test that? Regarding the other material. Frankly, I don't kno...
Regarding the weird looking malachite, this mineral is readily soluble in weak acids. So it should reacht with hydrochloric acid. Did you test that? Regarding the other material. Frankly, I don't kno...
1
REPLY
934
VIEWS
Started by Oberfuhrer
What is the maximum and minimum sampling interval that is suitable for drill cores from a first phase drilling in a porphyry Cu-Au deposit?
What is the maximum and minimum sampling interval that is suitable for drill cores from a first phase drilling in a porphyry Cu-Au deposit?
Last replied to by Paul Morrow
There is no simple answer to sample length, you need to consider geology, mineralisation, structural controls, drilling methods, mining methods, sample preparation techniques and ultimately is the cop...
There is no simple answer to sample length, you need to consider geology, mineralisation, structural controls, drilling methods, mining methods, sample preparation techniques and ultimately is the cop...
1
REPLY
1308
VIEWS
Started by Kumar Choudhry
I am wondering about correct sampling procedure from a Full 30 tonnes Dump-truck of Iron ore with the top size of 30-35 Cm. would someone kindly help me to provide any literature.This sampling is required to provide the proper feed to the beneficiati...
I am wondering about correct sampling procedure from a Full 30 tonnes Dump-truck of Iron ore with the top size of 30-35 Cm. would someone kindly help me to provide any literature.This sampling is required to provide the proper feed to the beneficiati...
Last replied to by Jean Rasczak
What you are suggesting is a very tough sampling problem at that top-size - much like the problem of draw-point sampling in underground cave mining methods.Unfortunately sampling theory would indicate...
What you are suggesting is a very tough sampling problem at that top-size - much like the problem of draw-point sampling in underground cave mining methods.Unfortunately sampling theory would indicate...
3
REPLIES
912
VIEWS
Started by Subhash-Kumar-Roy
Please could any one assist me in sampling procedure of Tailing dumps and low grade plies?
Please could any one assist me in sampling procedure of Tailing dumps and low grade plies?
Last replied to by
It is essential to separate tailings, or other fine-grained material amenable to easy coring, from low grade stockpiles, or any other waste rock heap, which is particularly challenging to sample. It m...
It is essential to separate tailings, or other fine-grained material amenable to easy coring, from low grade stockpiles, or any other waste rock heap, which is particularly challenging to sample. It m...
4
REPLIES
1562
VIEWS
Started by Obersturmbann
I’m just wondering if anyone knows any good papers on the QA/QC of assay data.To date I have only been able to find one "Quality Control of Assay Data: A Review of Procedures for Measuring and Monitoring Precision and Accuracy" by Marat Abzalov, wh...
I’m just wondering if anyone knows any good papers on the QA/QC of assay data.To date I have only been able to find one "Quality Control of Assay Data: A Review of Procedures for Measuring and Monitoring Precision and Accuracy" by Marat Abzalov, wh...
Last replied to by Obersturmbann
Thank you for the suggestions and help gentlemen, I'll follow them up in the next few days. If I come across any similar open source papers I will share them through this forum.
Thank you for the suggestions and help gentlemen, I'll follow them up in the next few days. If I come across any similar open source papers I will share them through this forum.
2
REPLIES
1287
VIEWS
Started by Helena Russell
Can anyone help me understand how to pin down possible reasons for getting only 37% of my original assays vs. pulp duplicates data plotting within 10% when I generate a HARD plot? I have over 400 pairs of data from three different labs. At each of th...
Can anyone help me understand how to pin down possible reasons for getting only 37% of my original assays vs. pulp duplicates data plotting within 10% when I generate a HARD plot? I have over 400 pairs of data from three different labs. At each of th...
Last replied to by
Unless your gold is very fine then you are likely to get a fair bit of noise from the pulp duplicates. The first thing to check is how is the duplicate pulp collected - if is taken from jus the top of...
Unless your gold is very fine then you are likely to get a fair bit of noise from the pulp duplicates. The first thing to check is how is the duplicate pulp collected - if is taken from jus the top of...
2
REPLIES
1049
VIEWS
Started by Oberstorm
What is the maximum and minimum sampling interval suitable for cores in a porphyry Cu-Au deposit?
What is the maximum and minimum sampling interval suitable for cores in a porphyry Cu-Au deposit?
Last replied to by
That is a good question. Porphyry Cu deposits are of very substantial size, and thus are typically mined using large-scale bulk tonnage methods. Consequently, ore blocks are usually estimated that are...
That is a good question. Porphyry Cu deposits are of very substantial size, and thus are typically mined using large-scale bulk tonnage methods. Consequently, ore blocks are usually estimated that are...
6
REPLIES
901
VIEWS
Started by Marshal Meru
I need some advice, in different process to sampling (croncretly), so determination of QA/QAC.
I need some advice, in different process to sampling (croncretly), so determination of QA/QAC.
Last replied to by Marshal Meru
I will visit this website. Do you know? I've some experience years in geologist. But now I want to be complete in different area in mining. I 'm based for moment in Burkina Faso.
I will visit this website. Do you know? I've some experience years in geologist. But now I want to be complete in different area in mining. I 'm based for moment in Burkina Faso.
3
REPLIES
2424
VIEWS
Started by Obergruppenfuhrer
I am among those with serious doubts about statements of absolute scientific truth. In reality we only process models of truth to enable us to rationally predict outcomes and connections to currently accepted science. This point of view categorically...
I am among those with serious doubts about statements of absolute scientific truth. In reality we only process models of truth to enable us to rationally predict outcomes and connections to currently accepted science. This point of view categorically...
Last replied to by
I was curious as to whether there would be much comment on this.Given that you went to the conference on Sampling Theory I presumed you would be in a position to answer your own question; however I no...
I was curious as to whether there would be much comment on this.Given that you went to the conference on Sampling Theory I presumed you would be in a position to answer your own question; however I no...
7
REPLIES
1316
VIEWS
Started by
http://is.gd/mQyFQ0. - I was contacted by this start-up the other day and wondering if anybody has been involved in any testing and could give some independent feedbackUnique Volume Instruments for Drill Core Scanning. Minalyze develop volume instru...
http://is.gd/mQyFQ0. - I was contacted by this start-up the other day and wondering if anybody has been involved in any testing and could give some independent feedbackUnique Volume Instruments for Drill Core Scanning. Minalyze develop volume instru...
Last replied to by
The question about the thickness of investigation of pXRF is essential, and can be easily linked with the statistical meaning of the cylindric shape of a core, its splitting, and the issue of lab/pXRF...
The question about the thickness of investigation of pXRF is essential, and can be easily linked with the statistical meaning of the cylindric shape of a core, its splitting, and the issue of lab/pXRF...
10
REPLIES
2279
VIEWS
Started by
Today I updated to sampling site image to a thing still done on may mine sites - sampling a dumped load of ore anything from 50 to 100 t or more in a pile.The usual process is collect a number of fragments from the pile then assign the "maybe" materi...
Today I updated to sampling site image to a thing still done on may mine sites - sampling a dumped load of ore anything from 50 to 100 t or more in a pile.The usual process is collect a number of fragments from the pile then assign the "maybe" materi...
Last replied to by
Some time ago I had to design a sampling exercise for a large old (more than 30 years since the mine closed) waste rock dump of material that contained disseminated monazite and sulphides in some of t...
Some time ago I had to design a sampling exercise for a large old (more than 30 years since the mine closed) waste rock dump of material that contained disseminated monazite and sulphides in some of t...
6
REPLIES
2153
VIEWS
Started by
RC Open pit grade control - how many benches? How far ahead in space and timeWhat's a workable number of benches to drill using RC or grade control? Say the benches to mine are 5 m. Three benches or four in one pass? Why? How much to drill in front o...
RC Open pit grade control - how many benches? How far ahead in space and timeWhat's a workable number of benches to drill using RC or grade control? Say the benches to mine are 5 m. Three benches or four in one pass? Why? How much to drill in front o...
Last replied to by Bob Mathias
Provided the Resource holes are done with a similar drill method and hole size as your grade control drilling (ultimately QQ plots to ensure no bias between drill programmes) then Yes use your Resourc...
Provided the Resource holes are done with a similar drill method and hole size as your grade control drilling (ultimately QQ plots to ensure no bias between drill programmes) then Yes use your Resourc...
I picked rubble from the ground and took 100g sample for fire assay. The result was 26g/ton. That is quite encouraging