Mineralogy, chemical and isotope composition of lead beads from Frobishers assay site, Kodlunarn Isl

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Mineralogy, chemical and isotope composition of
lead beads from Frobishers assay site, Kodlunarn
Island A parallel to the Bre-X scandal?

• Georges Beaudoin Réginald Auger
• Université Laval

Published in the Canadian Journal of Earth
Sciences (2004) v. 41 669-681
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Frobishers 3 voyages

• 1576 Discovery
• 1577 Return with 3 ships
• 1578 15 ships, 458 men equiped for mining

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Assays in England(1576-1579)

• 0 or ... 7 to 407 ppm Au
• 623 to 2022 ppm Ag

Gold and silver in rocks mined on Kodlunarn Is.

• Up to 14 ppb Au
• Up to 175 ppb Ag
• Hogarth and Loop (1986)

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Where all this gold came from?

• Contamination of assays gold in  fluxes  and
   ingredients 
• Fraudulent assays gold purposedly added to the
  assay load

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Musée canadien des civilisations
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• Shop 2
• Charcoal
• Crucible and cupel fragments
• Refractory ceramic

• Shop 1
• Coal
• Crucible fragments

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Shop 1
Shop 2
1398
2002
1413
1 cm
2278
1987
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Lead
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Chemical composition of lead beads(ppm)
ICP-MS
Assay
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In situ analyses (ppm)
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What gold grade?

• 0.7 ppm Au x 16 g of Pb 1.12 x 10-6 g Au
• If crucible contained 500 g of rock
• 1.12 x 10-6 g Au / 500 g 2.2 ppb Au

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1413
1398
2278
2002
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Lead compostion

• Shop 1
• Ag, no Au
• No Bi, low Cu, high Sb
• England?

• Shop 2
• Ag, trace Au
• High Cu, Bi, low Sb
• Cyprus?

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Where all this gold came from?

• Contamination of assays gold in  fluxes  and
   ingredients 
• Au improbable Ag at least partly

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Stefansson and McCaskill 1938, p. 151
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Where all this gold came from?

• Contamination of assays gold in  fluxes  and
   ingredients 
• Au improbable Ag at least partly
• Fraudulent assays gold purposedly added to the
  assay load

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Historic assays
Nov., Dec. 77, Feb. 78
Feb. 79
Feb. 78
Feb. 78
Feb. 78
Feb. 78
Mar. 78
Mar. 78
Feb. 78
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Historic assays
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How much gold ?
284 g or 9.1 oz.
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Conclusions

• No significant contamination
• Assays in England were  salted 
• Why and how by different assayers?
• Mixture of personal interest, gullibility, greed
  and, perhaps, crookedness, added to a certain
  measure of incompetence
• Same human flaws as those exposed in the Bre-X
  case, because nothing beats finding a GOLD MINE!

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Thank you!

• Bernard Allaire
• Social Science and Humanities Research Council
• National Science and Engineering Research Council
• Fonds pour la Formation des chercheurs et laide
  la recherche (FCAR)