|Diamonds Are Forever –
Most of the Time!
Prep for Teachers
Before teaching this lesson, make certain that all of your Web sites are bookmarked on all of the computers in your classroom, and that all of the necessary links are still valid and running. Make sure that each lab station has all of the necessary components in place for the start of the lesson. Prepare the four supersaturated solutions as shown on the Solutions Prep Sheet. You will need these for the Introductory Activity for this lesson unit.
| Duplicate all worksheets needed for the lesson before class begins including the How Does Your Crystal Grow, Salol Lab & Application Questions, Carbon Crystal Lab, and Crystal Internet Quest. You may also want to duplicate the Creating a Video Record of Your Project information included in the Student Materials. This provides a step-by-step guide for creating and editing a video using Adobe Premiere software.When using media, provide students with a FOCUS FOR MEDIA INTERACTION, a specific task to complete and/or information to identify during or after viewing of video segments, Web sites, or other multimedia elements.
How Does Your Crystal Grow…
Divide your students into lab pairs. Assign each pair a random number from 1 through 4. You will want at least 2 lab pairs for each number 1-4.
Distribute a paper towel, a long strip of tape, and 2 Petrie dishes with covers to each group.
Distribute a sheet of aluminum foil to 1/2 of the groups having each number. If there are two group #2s, one group gets foil, etc.
Have the students place their paper towels on the window sill or near a heat source on a table. Open the towels and write their names and class period on the towel. Place both Petrie dishes on the towel with the lid under one, and the lid to the side on the other. If they were given aluminum foil, it is to be placed under the open Petrie dishes – shiny side up.
Arrange for all of the #1’s to be together, the group 2’s, 3’s, etc. Now assign the numbers 1-4 randomly to the four colored solutions. Carefully pour the hot solutions into the Petrie dishes according to their numbers. Have the students place the covers over the one open dish which does not have the lid under it. IMPORTANT: NO ONE is to TOUCH or MOVE the Petrie dishes from this point on!
Have your students make their predictions for which crystals will form first, both color and whether it will be in a dish that is open or closed, on foil or toweling. They should also try to draw the shape they think the crystals will have.
Have the students make an observation at the start and close of class each day for the next three days. They need to look at all of the Petrie dishes and record their observations on the sheet provided for this activity. Please take time to discuss their findings and draw a general conclusion about the substances and the crystals formed.
Introductory Activity 2:
Build An Atom of Carbon!
Have the students break up into pairs to use the computers. Go to the website http://www.pbs.org/wgbh/nova/diamond/insidestable.html : The Atom Builder Guide to Building a Stable Atom. Explain to the students that they are going to start with a stable hydrogen atom and make it into a stable helium atom. Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to write down the steps they had to go through to make a proton. Allow the students to work independently to make the helium atom. Circulate to make sure they are getting the correct order of steps. Stop the students as a class to go over what must be done to make a proton and then a stable atom.
Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to list the number of protons, electrons, and neutrons found in one atom of lithium, beryllium, and carbon. Allow students to work in their pairs to complete the atoms and lists. Stop the class and discuss their lists. Discuss with them how many electrons are in the outer energy level of carbon and how many it would take to completely fill the outer energy level. (There are 4 electrons in the outer shell and it will hold a maximum of 8. This means carbon is free to share electrons with as many as four other atoms in its usual bonding configuration. Sometimes only two atoms of carbon will bond together, each sharing all four electrons with the other. )
Place the video in the VCR and CUE it to the start of the tape as the introductory credits say Thank You and the screen turns dark with the words “Narrated by Stockard Channing” appear. Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to list 2 particular properties of diamonds. PLAY the tape until you see the visual of the De Beers Millenium Star being turned by hand to show the sparkle and the narrator asking, “But what makes any diamond valuable?” PAUSE the tape to discuss what properties the narrator has discussed. Be sure to note all of the class properties on the board for them to check their notes against. (Class lists should include 1) A diamond is the hardest natural substance on Earth. 2) Diamonds are among the oldest materials on Earth.)
Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to listen for information about why diamonds are accidents of nature if they are made of the very common material carbon? PLAY the tape until you see the visualof an erupting volcano with the narrator saying, “ Diamonds should not exist. They are an accident of nature.” STOP the tape to check for student understanding. (Be sure that they understand that the bonds between the carbon atoms of coal are different from those between the carbon atoms of a diamond.)
FAST FORWARD the tape to the visual of the volcano erupting immediately after the footage of the diamond dealer. The audio will be, “There is power in diamonds.” Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to try to find out what the secret of a diamond is. They also need to be able to explain what it takes to turn coal into diamonds. PLAY the tape until the footage of the volcano erupting starts again. The narrator should be stating, “In some sense, it takes the entire planet earth to turn coal into diamonds.” PAUSE the tape to check for student comprehension. (All students should understand that it takes extreme heat and pressure to reshape these bonds.)
Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to listen for where diamonds are formed and how do they reach an area so that we might find them. PLAY the tape until the visual again shows a volcano erupting with the narrator saying, “rockets to the surface carried by high speed volcanos.”
PAUSE the tape to be sure that the student understand that diamonds are not formed in
the crust, but rather 100 miles beneath the crust in the mantle. They are carried to the surface of the Earth by high-speed volcanoes.
Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to write down their approximation of how old diamonds are before you restart the tape. Ask them to also listen for why diamonds are so important to a geologist. Warn them to pay particular attention to the pictures of what the raw diamonds look like. Please check to see that all students have a number written on their paper before you start the tape. PLAY the tape to the visual of raw diamond crystals being poured onto a surface pile as the narrator says, “To Taylor, a diamond’s true value is in what it can tell us about the distant past and the inner workings of the planet.” STOP the tape to discuss what the students have just learned. (Be sure that they understand that diamonds are the only hard sample we have of the deep interior of the Earth. A diamond does not change over time. Diamonds are dated by the material they “include”. Diamonds are generally regarded to be between 2 and 3 billion years old. The entire planet Earth is generally accepted to be 4.6 billion years old, making diamonds one of the oldest materials on Earth.)
FAST FORWARD the tape to the visual of blue plastic tubs of raw diamonds being wheeled down a hallway and poured out as the narrator says, “Every week hundreds of tubs carry thousands of carats worth millions of dollars.” Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to draw the basic shape of an individual diamond crystal from the information they have already seen and the clip they are about to view. PLAY the tape and you may wish to PAUSE the picture to show one individual crystal being weighed at 6.549 carats. STOP the tape as the diamond grader shows a pink diamond with calipers and says that “the color is that beautiful bubblegum pink.” Check the student drawings to see that they have a shape similar to two four sided pyramids joined base to base, an octahedron.
The class is now ready to start the Hands-on Learning Activity titled: Carbon Structures Lab.
Learning Activity 2:
Carbon Structures Lab
LEARNING ACTIVITY 3
FAST FORWARD the tape to a scene of white diamonds being poured like water over a black blackground. The audio portion should be saying ,”But that’s not all diamonds could do.” Provide students with a FOCUS FOR MEDIA INTERACTION by asking them to write down the two properties which diamonds possess which make them very important materials for the future. PLAY the tape through the visual of the De Beers Millenium diamond turning on its stand. STOP the tape and check for student comprehension. Be sure that they understand that diamonds are excellent conductors of heat but do not conduct electricity. The electrons actually pile up on the tip of the microscopic crystals and eventually jump to another structure! You are now ready to run the culminating activity for this lesson unit.
Have students look at another member of the carbon family and its bonding structures. Silicon and oxygen bond to form a silicate tetrahedron which is the basic building block of the silicate mineral family, the most common rock forming minerals on earth. How do the bonding structures relate to those of the carbon family? Research this on the internet.
Have students complete the Crystal Internet Quest
Have students research the use of various crystalline gems in jewelry, and create a design using diamonds, and or other gemstones. Have them explain their use of all specific gemstone types.
- Encourage students to investigate local mineral resources/mines. Go on a field trip to any local mineral points of interest such as the Sterling Mineral Mines of Ogdensburg, New Jersey.
- Ask students if any members of their family or friends are involved in a mineral based industry or profession. Schedule guest speakers as a part of a job-fair day
for the class.