by Jennifer M. Drewry
adapted from January/February 2000 Issue - Blacks in the Gold Rush

In 1848, when gold was discovered in California, people "rushed" from all over the United States to get some of the valuable metal for themselves. But why is gold so precious?

Gold is unequaled in its ability to be molded into any shape imaginable. For example, one ounce of gold can be stretched into a thin wire five miles long. That same ounce of gold can be hammered into a thin, 100-square-foot sheet.

Another outstanding quality of gold is its immunity to the corrosiveness of oxygen. Most metals, when exposed to air, will tarnish or lose their bright finish. Some metals will rust - changing colors and becoming brittle as well - as the oxygen breaks down the metal. Gold, on the other hand, does not lose its luster, nor does it become brittle.

Here's an experiment you can try. Since salt is also a corrosive element, we have added it to water to speed up the process.

NOTE: Please get an adult's permission first!

You need:

• 3 cups cold tap water
• 3 tablespoons salt
• measuring cup and spoon
• pitcher and long-handled spoon
• piece of gold jewelry with no stones or other pieces of metal on it (Make sure it is stamped 14k or 18k - a mark that indicates the gold content.)
• super-fine steel wool with NO SOAP
• 1-inch piece of copper tubing (can be purchased at a hardware store)
• pen, paper, and ruler to record your observations
• 3 glass bowls and 3 paper plates

Directions:

1. Pour the water into the pitcher and add the 3 tablespoons of salt. Stir the mixture well with the spoon.
2. Carefully examine the gold piece, the steel wool, and the copper pieces. Use the pen, paper, and ruler to make a chart similar to the one shown below. In the row marked "Day 1," record the color, brightness, and feel of each item.
3. Place one item into each glass bowl and pour enough salt/water mixture into each bowl to cover half the item. NOTE: Half of each item should be above the water.
4. Let each item sit in the bowl overnight - in a safe place.
5. The following morning, remove each item from the water and place it on a paper plate. Examine the items. Do you notice any changes in the gold? the steel wool? the copper? Write the changes in the row marked "Day 2."
6. Place each item back in its bowl, and let sit for a week.
7. On Day 8, repeat Step 5. Also test to see if any item breaks apart easily.
8. Compare your observations for Day 1, Day 2, and Day 8. How has each item changed? Which changed the most? the least? What do you think would happen to each piece if it stayed longer in the salt/water mixture? Which item is the most durable?

	Gold	Steel Wood	Copper Tubing
Day 1
Day 2
Day 3