1. Metallurgy Group David Dobbs Scott Jones Minh Nguyen Marc Rubin

2. Objectives Extract metals from ore Create efficient die Create coin using the metal

3. Procedure History of making bronze Make crucible from clay Measure amount of chemicals Metallurgy, using bronze to make coins.

4. History of Bronze First signs of Bronze Uses of Bronze in Ancient cultures Methods of making Bronze -ancient -modern Fun Facts “Bronze”. Microsoft Encarta Online Encyclopedia 2001. http://encarta.msn.com (25 Sept. 2001).http://encarta.msn.com

5. First Signs of Bronze 3500 BC-First created by the ancient Sumerians. 3000 BC-Bronze spreads to Persia. 2000 BC-Bronze in China and Egypt. 650 BC-330 AD- Hellenistic culture uses bronze. “Bronze”. Microsoft Encarta Online Encyclopedia 2001. http://encarta.msn.com (25 Sept. 2001).http://encarta.msn.com

6. Use of Bronze Ancient use: The accidental discovery of bronze in cooking fires. China: Pour metal into molds for spoons and/or pottery. Greece/Rome: Used to forge coins and make weapons.

7. Bronze making process Ancient: accidentally made when rocks with natural tin and copper ore were used as the campfire ring. Modern: The tin and copper are first “roasted”- blowing oxygen across the heated metal ore to get rid of impurities. Both: heat until over 1000°C to combine the 2 metals.

8. Fun Facts The bronze our group constructed destroyed steel. We used 15 tons of pressure from a hydraulic pump to mash the bronze into a coin between 2 plates of steel. End result: the bronze made a lasting indention in steel: (picture)

9. 15 tons of pressure + bronze = destroyed steel

10. Making a Crucible From dirt to clay. Shaping your crucible. Dry it. Add the chemicals. FIRE!

11. From Dirt to Clay Grinding the dirt into powder. Adding water.

12. Shaping Your Crucible Different methods presented to us.

13. Dry it Leaving it out over night. Drying in the oven.

14. Add the Chemicals Layering the chemicals.

15. FIRE! The kiln. Chemical reactions.

16. Mixing Chemicals We Want to obtain bronze. Mix copper carbonate(CuCO 3 ) and tin oxide(SnO) in a 5:1 ratio Weigh chemical compounds -5 g.CuCO 3 and 1 g. SnO -3 g. of Na 2 CO 3 -5 grams of charcoal (C)

17. Mixed Chemicals CuCO 3 and SnO Na 2 CO 3 Charcoal (C)

18. Placing Compounds in Crucible Lowest layer mixture of CuCO 3 and SnO Middle layer, flux Na 2 CO 3 Top layer, charcoal

19. Chemical Equations 2 CuCO 3(s) + C (s)  2 Cu (s) + 2 CO 2(g) 2 SnO (s) + C (s)  2 Sn (s) + CO 2(g) Compounds layered in crucible are placed in kiln The compounds are heated in an oxidizing atmosphere at 1000 °C.

20. Chemical Equation Cont. Na 2 CO 3 is used as a fluxing agent Pure metal ores, copper and tin come together to form bronze.

21. Eureka We have created a metal bead from the ore.

22. Making the Die Anything etched in the die will create a mirror image. We made a smilie face on one side and “CC” on the other side.

24. Making the Die We used a punch, drill and chisel to etch our image into the end of the punch.

25. Striking the Coin It was necessary to heat the metal bead with a torch. Then we whacked it.

26. FINAL PRODUCT Just kidding

27. Final Product