# Pigment Dates and the Anachronism Test > A pigment first manufactured in 1918 cannot be in a picture dated 1914. That asymmetry has broken more forgeries than connoisseurship, and it acquits nobody at all. > The Study - 2026-08-02 > Canonical HTML: https://iconotheca.com/study/pigment-dates-and-the-anachronism-test/ ## Key points - Industrial production of titanium white composite pigments began in November 1918 at Fredrikstad in Norway, which is the boundary that convicted a Campendonk dated 1914. - Prussian blue is documented in a dated painting of 1709 and in two Watteau paintings of about 1710, so the textbook exclusion boundary of the 1720s is roughly fifteen years too late. - The Courtauld's Procuress returned no modern pigments when analysed in 2009 and was confirmed as a van Meegeren in 2011 by the presence of Bakelite. - Knoedler sold twenty-four of thirty-one paintings supplied by Glafira Rosales, and the materials evidence was decisive across the group rather than reliably picture by picture. ## The asymmetry: an anachronism convicts, a clean result acquits nobody ## The dates that carry weight, and how they move ## Beltracchi: every test anticipated except the white ## Van Meegeren, Bakelite, and the measurement that finally closed the case ## Knoedler: materials convicted a group more surely than a picture Treat a pigment date as a boundary and never as a signature. Ask three questions of any report that offers one: where in the layer structure the sample sits, whether that layer is original or a restoration, and what the earliest evidenced use of the material is rather than its conventional textbook date. Answered properly, the method retires pictures with a finality no eye can match, and Beltracchi retired himself with a white he had no reason to reach for. Answered loosely, it produces the most dangerous document in the trade: a scientific report stating that nothing was found, read by a buyer as though it stated that something was proved. ## Questions **Does a modern pigment in a sample always condemn the painting?** No. Retouchings, later additions, lining adhesives, varnishes and surface grime all carry modern materials, and a swab or a surface reading cannot distinguish them from original paint. A condemnation requires the anachronistic material in an original layer, demonstrated in a cross section that shows where it sits in the stratigraphy. **Why is titanium white treated as such a reliable marker?** Because its industrial history is documented to the month, beginning with composite pigments at Fredrikstad in November 1918, and because titanium gives an unmistakable signal in X-ray fluorescence. The production process can also be read from the same spectrum: niobium is an impurity of the sulfate route only, so its absence indicates a rutile pigment and a date after 1959. **If a picture contains only period-correct pigments, is it authentic?** That does not follow. Skilled forgers buy or prepare period materials, and the Courtauld's Procuress passed a pigment examination in 2009 before Bakelite was found in it. A clean pigment result narrows the field of possible forgers rather than establishing an author. **What is the difference between a pigment date and a radiometric date?** A pigment date is documentary: it fixes the earliest year the material could have been bought. A radiometric measurement of lead-210 against radium-226 in lead white estimates how long ago the lead was smelted, which is a physical property of the sample and does not depend on any manufacturer's records. The two are independent, which is why the radiometric result settled the van Meegeren dispute. ## Sources - [1] Jens Bartoll, 'The Early Use of Prussian Blue in Paintings', 9th International Conference on NDT of Art, Jerusalem, 2008. - [2] B. A. van Driel, K. J. van den Berg, J. Gerretzen and J. Dik, 'The white of the 20th century: an explorative survey into Dutch modern art collections', Heritage Science 6, 16 (2018). - [3] ColourLex, 'Lead-Tin Yellow' and 'Ultramarine Artificial' (tertiary compilations, used here only for the two pigment types and for first and last dates of use; both should be replaced by the primary pigment literature, in particular Hermann Kuehn's 1968 study in Studies in Conservation). - [4] Diana Blumenroth, Jenny Nieberle and Gunnar Heydenreich, 'Moeglichkeiten und Grenzen kunsttechnologischer Untersuchungen: Heinrich Campendonks Gemaelde im Kontext des Beltracchi-Faelschungsskandals', CICS, Fachhochschule Koeln, 2014. - [5] The Art Newspaper, 'How the detection of titanium white gave away Beltracchi', 1 December 2012 (Nicolas Eastaugh). - [6] Winterthur Museum, 'Fooling the Experts: Han van Meegeren', in Treasures on Trial: The Art and Science of Detecting Fakes (2017). - [7] Bernard Keisch, The Mysterious Box: Nuclear Science and Art, US Atomic Energy Commission (Project Gutenberg edition). - [8] Laura Gilbert, 'More victims of Abstract Expressionist fakes scandal revealed', The Art Newspaper, 21 November 2013 (buyers and prices from Knoedler's court filing). - [9] The Art Newspaper, 'Red flags were flying around Knoedler fakes, experts testify', 4 February 2016. - [10] Winterthur Museum, 'The Knoedler Gallery Case', in Treasures on Trial (2017).