Unit 7 GEOS

Pre-Columbian History of Gold, Silver, and Other Metals

  • Four Stages of Metallurgical Evolution:

    • Stage I (Native Metals).

    • Stage II (Reduction, Smelting, Melting, and Casting).

    • Stage III (Use of Alloys).

    • Stage IV (Smelting of Sulfide Ores).

  • Attraction of Gold to Pre-Columbian Cultures: Due to its divine origin, color, shine, and sound, making it suitable for ornaments and sacred artifacts.

  • Placer Deposit:

    • A river deposit or sedimentary concentration formed by erosion and transport processes.

    • Concentrates minerals resistant to weathering and that are heavy, such as gold, silver, diamonds, and garnets.

  • Pre-Columbian Hard Rock Mining: Used stone tools, fire-setting, and manual labor to break rock and extract ores like gold, silver, and copper for smelting.

  • Huayrachina (Huaira):

    • A small, wind-powered clay furnace used in the Andes to smelt silver and copper ores.

    • Pre-Columbian peoples, especially the Inca, built them on windy ridges to harness natural airflow for high heat.

    • Essential for producing metals for tools, ornaments, and ritual objects.

  • Lost-Wax Casting (Cire Perdue):

    • An ancient metalworking method used to make detailed objects.

    • Process: A wax model is sculpted, coated in clay or plaster to form a mold, then heated so the wax melts away. Molten metal is poured into the hollow cavity, cooled, and the mold is broken to reveal the piece.

    • Practiced for thousands of years worldwide, allows fine detail, and is still used today for art, jewelry, and precision parts.

  • Bronze:

    • An alloy primarily of copper, with additions of tin, arsenic, phosphorus, and small amounts of other elements.

    • Pre-Columbian cultures used bronzes created by melting copper and adding elements like arsenic, tin, and phosphorus.

  • Metallurgy Development Regions:

    • Euro-Asiatic regions (7800 B.C. to 1200 B.C.).

    • The Great Lakes Region (4500 B.C. to 1000 A.D.).

    • Latin America (600 B.C. to 1500 A.D.).

    • The notes do not detail how knowledge spread between Andean and Mesoamerican cultures.

  • Pre-Columbian Metal Use: Primarily for ornaments and sacred artifacts, and later, copper and bronze were employed for tools and weapons.

  • Mesoamerican Metallurgy Development: The provided notes do not summarize the development of metallurgy specifically in Mesoamerica (Mexico) with details on trade, initial, and last/second periods.