properties. Millillg for...
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ES4b. Students know how to identify common rock-forming minerals (including quartz, calcite, feldspar, mica, and hornblende) and ore minerals by using a table of diagnostic properties. INVESTIGATION 2 . Millillg for Millerala Gold • 0 you know what a 4ger is? That's the nickname given to people who poured into Califor?ia in 1849. Why did they come? Gold! Gold was discovered in a stream in Coloma, California, in 1848. It was in the form of nuggets. You could scoop up a pan full of stream gravel and wash the gravel away. This would leave the heavy gold in the pan. In a few years the California gold country was full of thousands of gold panners trying to strike it rich. Before too long the gold was panned out. Was all the gold gone? No. The rocks still held a lot of gold ore. Ore is any rock or mineral that has a valuable substance in it. Gold ore has gold in it. Silver ore has silver. Iron ore has iron, and so on. The search for gold changed from panning to mining. Gold miners used dynamite and shovels to get the ore. Sometimes they dug deep tunnels to get the gold. Big machines crushed the ore. The miners then separated the gold from the rest of the minerals. 190
Transcript of properties. Millillg for...
ES4b. Students know how to identify common rock-forming minerals (including quartz,calcite, feldspar, mica, and hornblende) and ore minerals by using a table of diagnosticproperties.
INVESTIGATION 2 .
Millillg forMillerala
Gold
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0 you know what a 4ger is? That's the nickname given topeople who poured into Califor?ia in 1849. Why did theycome? Gold!
Gold was discovered in a stream in Coloma,California, in 1848. It was in the form ofnuggets. You could scoop up a pan full of streamgravel and wash the gravel away. This wouldleave the heavy gold in the pan. In a few yearsthe California gold country was full of thousandsof gold panners trying to strike it rich. Beforetoo long the gold was panned out.
Was all the gold gone? No. The rocksstill held a lot of gold ore. Ore is any rock ormineral that has a valuable substance in it. Goldore has gold in it. Silver ore has silver. Iron orehas iron, and so on.
The searchfor gold changed from panningto mining. Gold miners useddynamite and shovels to get theore. Sometimes they dug deeptunnels to get the gold. Bigmachines crushed the ore. Theminers then separated the goldfrom the rest of the minerals.
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&auxiteBauxite is a rock. It is made of three
minerals. Each of the minerals has themetal aluminum in it.
In many places around the world,bauxite is a red clay Bauxite depositsfound on or near Earth's surface arescooped up with big power shovels. Theore is crushed, screened, and groundinto powder. Then heat and electricityseparate aluminum out of the bauxite.
Aluminum is three times lighter than steel and almost asstrong. It is a good material for building bridges, airplanes,bicycles, and cars. Because it does not rust, aluminum is madeinto boats and siding for houses. It is also made into wire, cans,kitchenware, and foil for wrapping food.
Aluminum ore-bauxite
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lleview ."estiolls1. What is ore?
2. Which of the ores shown below could produce ametal you might find in a radio? Why do you thinkso?
3. Which ore could produce a metal that would make agood hammer? Why?
4. Which ore could produce a metal you would like towear? Why?
5. Which ore could produce a metal that would make agood airplane wing? Why?
6. Identify the four ores shown below.
a.
c.
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