Authenticity of medieval document tested by small particle analysis

The Vinland map, revisited: new compositional evidence on its inks and parchment

“…However, questions about its origins and authenticity were raised and have persisted since its discovery. For this reason, compositional studies were performed in 1974 by McCrone Associates (3,4) on 29 microparticles removed from the surface of the Map and 25 microparticles removed from two other documents, the Tartar Relation and the Speculum Historíale, that are possibly associated with the Map. The results of these studies were interpreted as showing that the Map was a 20th-century forgery, made by drawing the map twice, first in a yellowbrown line and then overdrawing this line with a black ink which was partially chipped away in order to simulate antiquity.…”

The Vinland Map: A Critical Review of Archaeometric Research on Its Authenticity*

“…Brown and Clark (2002) looked specifically for ilmenite in their Raman‐spectroscopic examination of the map and found none. McCrone (1974, 1976, 1988, 1996, 1999) did not report any by microscopic observation or any other test.…”

“…The calcite in the VM is ground limestone, and therefore not helpful in dating this map; most calcite in modern paintings etc. is the precipitated material’ (McCrone 1976). However, we now know that this distinction is questionable, since all calcites/limestones, when ground sufficiently well, produce CaCO 3 rhombohedra of about the same size and shape, regardless of their source (Reeder pers.…”

“…It doesn't seem to have worked very well, as McCrone and others guessed that 90–95% of the black ink drawing was lost (McCrone 1974), in rough agreement with Cahill's numbers. The loss was caused, simply, by the misguided cleaning efforts of an unknown person unskilled in conservation and not, as McCrone (1974, 1976 , 1988 , 1996 , 1999 ) has postulated, by a skilful forger laboriously abrading away 90–95% of a black ink line that they had placed, with an average error of ±0.1 mm down the middle of a previously inked yellow line measuring only about 0.5 mm in width.…”

Multiple Microanalyses of a Sample from the Vinland Map

“…Over the years, several studies of the Vinland Map and its ink have been made with the aim of determining its authenticity and condition (Washburn , ; Baynes‐Cope ; McCrone ; McCrone and McCrone ; Cahill et al ; Cahill and Kusko ; Olin ; Brown and Clark ; Donahue et al ; Seaver ; Guzman ; Larsen et al ; Harbottle ; Towe et al ; Larsen and Sommer ; Edwards ).…”