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Oak Island artifact collection
Artifact Colonial

Gold-Copper Alloy Fragments (Tumbaga)

Disputed: Pre-Columbian tumbaga (from c.300 AD) or Spanish-colonial rose gold (1550-1700)

Gold-copper tumbaga alloy fragments from Money Pit area
Gold-Copper Alloy Fragments (Tumbaga) — Disputed: Pre-Columbian tumbaga (from c.300 AD) or Spanish-colonial rose gold (1550-1700)
Photo: The HISTORY Channel
Location Money Pit area
Discovered Season 9 (2022)
Date Range 300 AD – 1700 AD
Category Artifact
Era Colonial

About This Artifact

Small fragments of gold-bearing metal recovered from the Money Pit area. Analysis by geoscientist Dr. Christa Brosseau revealed a composition of approximately 65 percent gold and 26 percent copper, with a small amount of silver. Brosseau identified the alloy as consistent with rose gold, but Marty Lagina noted the chemical composition also matched tumbaga, the gold-copper alloy widely used by Inca and Aztec civilisations and later melted down by Spanish conquistadors into bars. Tumbaga was not a single standardised alloy but an umbrella term for a range of gold-copper compositions, with gold content varying from as little as 3 percent to as much as 97 percent. The presence of a gold-copper alloy in the Money Pit does not confirm a South American origin, as copper-gold alloys also occur naturally and were produced in medieval Europe, but it is consistent with the Spanish Connection theory.

Historical Context

The Curse of Oak Island Season 9; Dr. Christa Brosseau analysis

Where It Was Found

Found at Money Pit area — the original 1795 excavation shaft on Oak Island, Nova Scotia.