Material Evidence: McCrone (1974)

Ink Closeup
A view (X 250) showing the components of the yellow ink line

2). MICROSCOPY 1974

McCrone investigates the composition of the VM ink.
McCrone, W. C. & McCrone, L. B. 1974 The Vinland Map ink. Geogrl. J. 140, 2 : 212-214.
McCrone, W. C. 1976 Authenticity of medieval document tested by small particle analysis.
Anal. Chem. 48, 676A - 679A.

BACKGROUND:

McCrone compared the map, VM, and the two associated volumes, TR and SH, using microscopy at high magnification. He removed some 50 particles from the surfaces, measuring their optical properties, particle size and shape, elemental composition, and molecular composition.

Microscope
Polarized light microscope for identifying particles in the ink

FINDINGS:

  • The ink on the TR and SH is iron gall ink. The ink on the VM is not iron gall ink.
  • The VM ink line is a black ink line (80% flaked off) traced over a yellow ink line. In places, the black ink line does not follow the yellow ink line.
  • Crystals of modern, synthetic anatase TiO2 are found on the VM - in the yellow ink but not in the black ink and not on the parchment.

COMMENTARY:

  • Iron gall ink is unstable over time, first staining the parchment yellow. Yellow coloration around an ink implies an iron gall ink that is old. The VM ink shows yellow coloration but it is not iron gall ink. Yellow coloration must have been added to suggest age.

QUESTIONS:

  • Do the results of McCrone and Baynes-Cope agree?
  • Does the evidence suggest a common origin for the Vinland Map and TR and SH?
  • Does the evidence suggest that the VM ink line is medieval or modern?
  • How could the VM ink line have been created to appear as it does today?