Format Class will be centered around doing a group Pre-Feasibility Assessment of a Hypothetical Ore Deposit – There will be one deposit this year – It will be assigned – You will work as a group with subteams and individual assignments – You will heavily use computer aides – particularly MineSight
More Organization First Task will be to select a team leader – They will directly report and work with me – The will also issue assignments within the group and report those assignments to me – If someone tries to take a free ride they will be the lead in turning you in. – Teams may discuss what they want to do, but if consensus is not reached team leader can make executive decision.
A Note on Workload The workload is not proportional to the credit hours – My example 15 credits – 3 of Senior Design – The time commitment 50% to Senior Design, 50% to everything else - ie about 4 times the logical level – Consolation prize We don’t necessarily have class everyday Unconsolation we have 4 classes for 3 credits
Working in Teams People Depend on you to complete your portion of the work – Your failings can screw other people (most of whom will not be happy about it) – Two negative side effects You will feel some peer pressure While grading is outlined and explained you will almost certainly feel some unfairness because not everything is in your control Some work will have to be graded by team I will also break down points by individual
Grading Senior Design Fixed % scale with no curve – 90% A – 80% B – 70% C – 60% D – <60% - the opportunity to repeat the class
Points Distribution Weekly oral reports 25% Weekly written reports 25% Work Performance Assessment 15% Final Oral Report 15% Final Written Report 20%
Oral Reports Once a week the team will do a powerpoint based oral presentation – This means public speaking – This means doing powerpoints – This means doing the work that you will report on Your team leader will order/consult with you on what the over-all content will be – Individuals will be appointed to give subparts of the presentation based on their work You’ll turn in a copy of your PP after presenting
Written Reports New Format this Year – A work journal with a summary report at the end – Each week there will be at least 3 written reports. You will explain what you did You will explain how it fits in to the over-all objective You will identify what you did to get information and where you got it You will indicate how you analyzed that data You will explain what your conclusions and resulting parameters were You will have appendices of the data you found or compilations of MineSight reports – Each with have a heading explanation of what it is and how it was part of the work done.
Written Reports Written reports will be turned in at the end of the presentation along with copies of the powerpoint show.
Work Performance Assessment Teacher’s arbitrary capricious tool for screwing you if you don’t do you work well by the time it is due. – If you convincingly show that you really did the work that was assigned to you during a given week its easy points – If you sit back till the last minute and then wait for the gods to come do your work – big mean teacher will clobber you with this. – (I have allowed student ratings of each other to be a part of this in the past)
Your Deposit is in Central Alaska It is in granitic type Mesozoic Igneous Rock
The Deposit is along the Yukon River west of Fairbanks Alaska near the busteling Metropolis of Ruby
There are Roads to Fairbanks (too bad about your deposit) Alaska has a backwoods road network between major cities, but other areas may have Only local roads that end and never connect anything.
The deposit is in rolling mountains amid flat low-lands. Lowlands are around 300 ft Mountains more like 1000 ft or so. Ruby sits on The banks of The Yukon River at 250 ft
Ruby Has its Own Airport Complete with a rutted gravel Runway 4000 ft long and 100 Ft wide. It even has its own windsock! Terminal Facilities give new Meaning to terminal
Alaska’s Advanced Road System. Road to Manley Hot Springs
The native fishing villages of Ruby and Tanana are in the area – Ruby is a checkpoint on The northern route of the Idicarod Trail (anyone for hauling concentrates by dog sled?) Roads do go to Manley Hot Springs.
An old gold mining boom town. Native Americans moved in when The boom population left A big 170 people today. Ruby Alaska Access is only by air, with river, dogsled and Backpacking by season. 83% Native American 14% White rest mixed race – considered a fishing village
Ruby has Its Own Electric System (Ruby Electric) Most communities have Non-interconnected Diesel generators In Ruby its Ruby Electric
Ruby Does Have a Phone System Here is the whole phone book
The Alaskan Railroad Goes to Fairbanks
Tanana Alaska Population 251
Precipitation is about 13 inches per year.
It is in Mesozoic volcanics
The area has thin to moderate permafrost under it.
Climate is Similar to Fairbanks (you might even make 73 degrees in July – of course -17 is the average Low in January)
You Might Be Comfortable 23% of the Time in June and July
You Can See the Sun in Winter
Most Precipitation is Light Rain or Snow
August Humidity is High but the Weather is Cool
Not a Particularly Windy Place
Winds Mostly out of the East and North East
Your Ore Your Highest Grade Metal is Copper – Your ore also contains some Gold and some zinc Your Deposit has 6 major mineral zones – An oxide zone on top (6) – An oxide to secondary sulfide zone (5) – A secondary Sulfide zone (4) – A secondary to primary transition (3) – Two primary sulfide zones (1 and 2) – (numbers are block model codes)
The Oxide Zone Your copper minerals – 30% of copper in Azurite – 15% in Cuprite – 55% in Chrysacola Gold is native a free milling coming out of limonite and geothite 76% of your silver is free milling metallic 12% of your silver is an impurity in the free milling gold 12% is substituted in Cu oxides
The Secondary Enrichment Zone Copper is in – 55% Chalcocite – 40% Covelite – 5% Chalcopyrite – Ag is 50% Acanthite, 25% Argentite, 12.5% substituted in Cu minerals and 12.5% mixed with gold Gold is 50% free milling and 50% encapsulated in pyrite
The Primary Zone – Zones 1 and 2 Cu minerals 70% Chalcopyrite 30% Bornite Ag is 37.5% in Argentite, 37.5% in Acanthite, 12.5% substituted in copper minerals, and 12.5% in mixture with the metallic gold – Zone 2 Gold is metallic, but 50% is encapsulated in pyrite (ie only 50% is free milling – Zone 1 Gold is metallic and 50% encapsulated in pyrite but there is enough “preg robbing carbon” to take up all the gold released by leaching 5 times over.
Transition Zones Zone 5 is 50% like zone 6 oxide and 50% like zone 4 secondary enrichment Zone 3 is 50% like zone 2 primary sulfide and 50% like 4 secondary enrichment.
Rock Strength and Strata The pit will normally sustain an over-all slope of 55 degrees Toe to Crest slopes of 75 degrees are sustainable A fracture pattern – a major structure strikes North 30 degrees East – The dip is 60 degrees to the north-west – The angle of internal friction on the fracture planes is 20 degrees
New This Year Your report will be a documented journal of how you reached conclusions and decisions Each Week you will submit an electronic report journal and do an oral presentation Reports of Week 1 Metal Prices, Climate and Workforce, Infrastructure and processing facilities
Metal Price Helps I have a USGS report that will give historic prices and discuss product uses and historical price drivers Just one problem – it gives historic prices – How does one adjust for inflation? – Use the Consumer Price Index – (I also have an electronic file for that)
Inflation Adjusting Prices In 1913 copper was 15.5 cents per lb The consumer price index was 9.9 Today the CPI is Adjust – 15.5 * / 9.9 = – Or $3.65 cents per lb
You are Also Required to Evaluate Relative Metal Values One way to look at the data is with MineSight Data Analyst
It Has a Built In Instruction Manual
Data Analyst is Used to Explore and Do Graphs on Things Like Block Models
How Might I Use This? Suppose I am looking at typical values for my primary sulfide ore Copper 0.325% Silver 0.04 oz/ton Gold 0.04 oz/ton Pyrite 1% Suppose I have determined copper is $3.25/lb, Ag $25/oz, Gold $1,200/oz One Tonne of ore 2205 lbs (metric tonnes) 0.325% * 2205 lbs = about 7 lbs Cu or a little less $23/ton Gold 0.04 oz * 1200 = $48/ton - about $24/ton in free mill and $24/ton pyrite Silver 0.04 oz * 25 = $1/ton – 75 cents in floatable sulfides 12.5 cents each in Gold and Cu substitute
What do I Know Gold is most valuable at $24/ton free milling gold will likely be a primary Processing target I have $24/ton in pyrite encapsulation and $23/ton in copper sulfides I’m thinking 2 stage floatation here Silver at 75 cents – I’ll have to see whether a 3 rd flotation stage is justified The rest will be substituted in other products – I’ll deal with it in smelter Credits.