1. 4000 20000 BCE Time (years) CE Stone Age Bronze ageIron Age The ages of civilization and Metal Consumption

2. Mineral Resource Consumption Copper Lead Iron Aluminium Zinc

3. Metal consumption – resources

4. Life expectancies of resources of selected commodities based on crustal abundance

5. Metal Recycling

6. Rates Metal Recycling

7. Metallic Mineral Exploration – Looking for the proverbial needle in the haystack

8. Black Smokers and Massive Sulphide Ore Deposits 350 o C CuCl ZnCl 2 PbCl 2 Chalcopyrite Sphalerite Pyrite (FeS 2 ) (CuFeS 2 ) (ZnS)

9. Black Smokers Fluids precipitate sulphide minerals on the walls of the chimneys (Pyrite, FeS2; Chalcopyrite, CuFeS2; Sphalerite ZnS).

10. Massive Sulphide Ore Formation

11. Black Smokers and Massive Sulphide Ore Deposits

12. Sphalerite Pyrite Pyrite and sphalerite Sphalerite Pyrite Chalcopyrite Sphalerite Pyrrhotite Massive Sulphide Ores

13. Hydrothermal vein deposits 1 cm Hot water dissolves metals as complex molecules, e.g. H 2 WO 4 or Hg(HS) 2. Quartz and metallic minerals precipitate in fractures in response to cooling or changes in water chemistry Cinnabar (HgS )  m 10 cm Hg-bearing quartz vein Fluid inclusion Wolframite (Fe,Mn)WO 4 )

14. Porphyry Copper deposits 1 cm Porphyry ore Brine (NaCl-H 2 O) exsolves from cooling diorite intrusion Cu dissolved as CuCl 2, Fe as FeCl 2 Reaction with H 2 S on cooling to form chalcopyrite (CuFeS 2 ) Open pit mine

15. Au(HS) 2 - + H + + 0.5 H 2 O = Au + 0.25O 2 + 2H 2 S Removed by boiling Native gold Formation of an epithermal gold deposit Gold-bearing quartz veins Native gold

16. Alluvial deposits Gold panning Gold nugget

17. Witwatersrand Goldfields Gold- bearing conglomerate (Produces 35% of world’s gold)

18. Understanding Planet Earth The Earth as a System