Teacher Developed Activity, T-DA!
Brian Croone and Linda Waagen
Activity Name: Understanding Mining “Eat Your Iron Ore”
Seminar: Building America
Grade Level: 7-12
For use with lessons about: Industrialization, Minnesota History/Geography, Westward
Expansion
Time Needed: 5 days
Materials :
 several bags of chocolate chip/chunk cookies (different varieties add challenge)
 several bags of Snickers or Milky Way candy bars (could adapt to other layered
candy bars)
 scale for weighing cookies, chips, caramel, and waste
 variety of mining “tools” – toothpicks, spoons, tweezers, plastic knives, small
brushes, etc.
 grid paper for measuring cookie and waste
 small cups for placing mined “ore” and “waste material” into (3 oz. Dixie cups)
 “Iron Mining for Kids” handout
 computers and or hard copy readings for research project (days3-5)
Overview :
This activity is designed to teach students the complexities of iron mining; the differences in
geologic formation of “hard” iron ore veins and taconite ore; the issues of efficiency,
profitability, waste disposal, and safety in obtaining useable iron ire.
Essential question: How can humans mine a non-renewable resource like iron and
maintain sustainability within the industry and communities?
Outcomes:
 Students will be able to describe hard rock mining; both underground and open-pit; and
taconite processing.

Students will be able to describe the geographic forces on the earth that created iron ores.

Students will be able to demonstrate decision making skills as they mine and decide on
proper “waste” disposal options.

Students will discuss the uses of iron historically and the limited availability of “cheap”
ores. Alternatives to “use and discard” and random dumping of possibly harmful tailings
will also be addressed.
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
Students will interpret historic maps and photographs to draw conclusions about the
impact of mining on the landscape and communities.

Students will discuss alternatives for communities when an ore “runs out” and mining is
no longer a viable means of employment for an area once dependent upon such an
industry. Other industries with similar issues will be discussed as well (timber, coal, fruit,
ranching).
Activity steps:
DAY 1:
Key Concepts: Pockets of iron ore provide rich materials and relative ease of retrieval.
Relatively large numbers of skilled and unskilled immigrants came to work in the mines.
1. Prior to the mining, students should read Iron Mining for Kids booklet (see PDF).
2. Discuss briefly the reading and explain the mining activity and its purpose.
3. Each student starts with a cookie, 2 small Dixie cups, and a record sheet. Students
weigh their cookie and record the weight in the proper space. They then select a tool
to “mine” the chips/chunks from their cookie, placing “ore” in one cup and waste in
another. Time students to simulate a mining “shift”. At the end of the allotted time or
“shift”, they weigh the “ore” and “waste” and record those weights in the proper
space.
4. Discuss the experience. What tools worked best? Problems faced in mining the “ore”?
What becomes of the waste (no, they can’t eat it yet)? Discuss the life of the miner –
buying their own tools, dealing with variety of rock, inconsistencies of ore deposits.
5. Mine again, only this time students are in groups of 4 and each has a specific task as
given on an index card by the teacher. (supervisor, blaster, picker, shoveler). Students
are given 6-8 cookies to mine in the set “shift” time. Record data before and after the
timing takes place. As in the mines, tell them they can’t talk but only gesture as the
noise and variety of languages made oral communication nearly impossible.
6. Discuss the differences between the on individual and group experience. What are the
benefits to cooperative groups? Discuss how miners created their own “mine
language” to be able to understand one another. (Yes, NOW they can eat the cookies)
7. Assign homework reading : Taconite mining information sheet (attached)
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DAY 2
Key Concepts – Taconite is found in a similar geologic strata to Iron Ore but on a much less
concentrated scale. Taconite mining for useable iron while feasible is a lengthy and costly
project.
1. Discuss the reading and show geologic cut-away slide to explain where hard ore is
found and where taconite is found. Review the mining from the previous day and
explain that today we will be in groups again and “mining” a more difficult material –
caramel from a snickers bar (for real layer experience, use a KitKat or other layered
cookie/candy).
2. Each student starts with a caramel layered candy bar – Snickers or Milky Way
(Snickers present the added challenge of the peanuts within the caramel layer – a
“waste” product hard to separate from the caramel, as is the chocolate) or similar bar
with a caramel layer, 2 small Dixie cups, and a record sheet. As in the previous
lesson, students weigh their bar and record the weight in the proper space. They then
select a tool to “mine” the caramel from their cookie, placing “ore (caramel) in one
cup and waste in another. Time students to simulate a mining “shift”. At the end of
the allotted time or “shift”, they weigh the “ore” and “waste” and record those
weights in the proper space. (To make it even more challenging, you could explain
that the taconite is actually only the sugar within the caramel and discuss ways to
possibly remove only the sugar. (Mixing with warm water to dissolve the caramel,
then letting the sugars crystallize on a string or other material while the moisture
evaporates is probably the best but would take quite a bit of time – which lets them
see the difficulty of taconite processing).
3. Discuss the experience. What tools worked best? Problems faced in mining the
“taconite”? What becomes of the waste (no, they can’t eat it yet)? What are some
potential problems of just “dumping” the wastes? What else can be done with the
waste? (Discuss the possibility of getting “ore” (sugar) from the waste material).
4. Discuss ways that might make removal of the caramel easier – i.e. freezing the candy
bar, melting the bar, etc.) Show slides of the taconite process and iron pellet
process.(See attached from Craig Hattam’s disc).
5. Discuss the differences between the ore “cookie” and taconite “caramel processing”
experience. How did the advent of machinery and computers change the way mining
could be done? How has the number of people working at the mines and the types of
jobs they do changed as technology changed? (Yes, NOW they can eat it)
6. Homework – write a paper 1 page in length describing the two types of iron ores and
the mining process. Include the various workers roles and historic timeframe for the
two mining activities.
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Day 3-5
Key Concepts– sustainability, multiculturalism, ecological impact, and profitability aspects to
iron mining
1. In small groups students will conduct internet research and discuss the concepts of
sustainability, multiculturalism, ecological impact, and profitability. (Each group
should be assigned one concept to research). Together they will produce a brief news
cast type skit to share their findings with the rest of the class and to invite questions in
a “press conference” type of setting. This can be as teacher directed or student
directed as the individual teacher is comfortable with.
2. On presentation day, set up room as if for a press conference and have students dress
up, use “microphones” and maybe even run a video camera!
Handout: “Iron Ores” background reading
Handout: “Underground Mining” and “Open Pit Mining”
Background Information:
http://miningartifacts.homestead.com/IronOres.html
Additional resources:
Economics and the Environment Curriculum: Minnesota Council on Economic Education
http://store.councilforeconed.org/ecanden1.html Click here for a sample lesson: What are
spotted owls, timber products and magical stones really worth?
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Underground Mining
http://miningartifacts.homestead.com/MNUndergroundMining.html
Cut and Fill mining is a method of short hole mining used in narrow ore zones.
An access ramp is driven off the main level to the bottom of the ore zone to be
accessed. Using development mining techniques a drift is driven through the ore
to the defined limit of mining. Upon completion the drift (or "cut") is filled back to
the access ramp with the defined type of backfill, which may be either
consolidated or unconsolidated. Another drift is driven on top of filled cut. This
process continues until the top of the stope is reached.
Drift and Fill is similar to cut and fill, except it is used in ore zones which are
wider than the method of drifting will allow to be mined. In this case the first drift
is developed in the ore, is backfilled using consolidated fill. The second drift is
driven adjacent to the first drift. This carries on until the ore zone is mined out to
its full width, at which time the second cut is started atop of the first cut.
Room & Pillar mining is commonly done in flat or gently dipping bedded ore
bodies. Pillars are left in place in a regular pattern while the rooms are mined out.
In many room and pillar mines, the pillars are taken out starting at the farthest
point from the stope access, allowing the roof to collapse and fill in the stope.
This allows a greater recovery as less ore is left behind in pillars.
Block Caving is used to effect with large sized orebodies which are typically
composed of low-grade, friable ore. The method works best with cylindrical,
vertical orebodies. Pre-production mining development work consists of driving
accesses underneath the orebody. This includes the formation of "drawbells" by
undercutting and blasting. Initially, blasted ore is removed via the extraction level
underneath the drawbells until a sufficient area of unsupported ore is formed that
the orebody begins to fracture and cave on its own. The eventual aim of the
block caving method is that the friable ore needs no blasting and continues to
fracture and break up on its own, flowing down the drawbells to the extraction
level, where it is removed from the ore chute mouths with loaders and sent off for
processing. Eventually the fracturing will propagate to the surface, resulting in
subsidence. One of the main hazards associated with block-caving is that
fracturing can potentially stop before it reaches the surface unbeknownst to the
people in control of the mine. If fracturing stops propagating upwards and
extraction continues, a large void can be formed, resulting in the potential for a
sudden and massive collapse and catastrophic windblast throughout the mine.
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The underground iron mines in Minnesota were shaft mines as opposed to drift
mines. Shaft mining refers to the method of excavating a vertical or near-vertical
tunnel from the top down, where there is initially no access to the bottom. When
the top of the excavation is at the surface, also known as "at ground", it is
referred to as a shaft, when the top of the excavation is underground it is called a
winze.
Underground Mining Methods
On the surface above the shaft stands a building known as the headframe (also
winding tower, or pit head). Depending on the type of hoist used the top of the
headframe will either house a hoist motor or a sheave wheel with the hoist
engine mounted in the. adjacent engine or winding house. The headframe will
also contain bins for storing ore being transferred to the processing facility. If the
shaft is used for mine ventilaton a plenum or casing is incorporated into the
headframe to ensure the proper flow of air into and out of the mine.
Head frame & engine house of the Mckinley Mine, McKinley, Mesabi Range, St. Louis
Co, MN
A mine shaft is generally split into multiple compartments. The largest
compartment is used for the cage, a conveyance used for moving workers and
supplies below the surface. It functions in a similar manner to an elevator. The
second compartment is the skip, used to transport ore to the surface. Smaller
mining operations use a skip mounted underneath the cage, rather than a
separate device. The third compartment is used for an emergency exit; it may
house an auxiliary cage or a system of ladders. An additional compartment
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houses mine services such as high voltage cables and pipes for transfer of
water, compressed air or diesel fuel.
The mine shaft is used to access an underground mining facility. Horizontal
workings off the shaft are called drifts, galleries or levels. These extend from the
central shaft towards the ore body. The point of contact between these levels and
the shaft itself is known as the inset or shaft station.
Main Station, Fayal Mine, Eveleth, Mesabi Range, St. Louis Co, MN
Miners and loaded ore car underground - Fayal Mine
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Loading an ore car in an unknown Minnesota iron mine
Miners lighting blasting fuse - Godfrey Mine, Chisholm, Mesabi Range, St. Louis Co,
MN
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Underground in an unknown Mesabi Range mine
Miners underground in unknown Minnesota iron mine
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Underground in an unknown Virginia, Minnesota iron mine
Notice the dynamite cases on the flat car to the left.
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Open Pit Mining
http://miningartifacts.homestead.com/MNOpenPitMining.html
Open-pit mining, also known as opencast mining and open-cut mining, refers to a
method of extracting rock or minerals from the earth by their removal from an
open pit or borrow.
The term is used to differentiate this form of mining from extractive methods that
require tunneling into the earth. Open-pit mines are used when deposits of
commercially useful minerals or rock are found near the surface; that is, where
the overburden (surface material covering the valuable deposit) is relatively thin
or the material of interest is structurally unsuitable for tunneling (as would be the
case for sand, cinder, and gravel). For minerals that occur deep below the
surface—where the overburden is thick or the mineral occurs as veins in hard
rock— underground mining methods extract the valued material.
Open-pit mines that produce building materials are commonly referred to as
quarries. People in some English-speaking countries are unlikely to make a
distinction between an open-pit mine and other types of open-cast mines, such
as quarries, borrows, placers, and strip mines.
Open-pit mines are typically enlarged until either the mineral resource is
exhausted, or an increasing ratio of overburden to ore makes further mining
uneconomic. When this occurs, the exhausted mines are sometimes converted
to landfills for disposal of solid wastes. However, some form of water control is
usually required to keep the mine pit from becoming a lake.
Biwabik Mine, Biwabik, MN - 1895
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Gilbert Mine, St. Louis County, Mesabi Range, MN - 1909
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