Dating instrument medical power radiography source
However, results on the canvas alone may be inconclusive, as canvas may have been reused by the artist himself as an economic measure or intentionally by a forger with the intent to deceive.The infamous Han Van Meegeren (1889–1947), who specialized in forging Vermeer paintings, is known to have scraped the paint off of older paintings to reuse the canvases to yield the illusion of a naturally aged painting substrate (16, 17).The triangle in continuous blue lines is a small extension of that loss to acquire a sample for the work reported here.If possible, conservators sample from existing losses or damages.In cases where no pigment, filler, or binder anachronisms are identified, the judgment of degradation products arising from natural aging is inconclusive, and radiocarbon dating of the support material is indecisive, dating of the binder in the pictorial layer is indispensable.
The GIS-AMS setup requires only minute amounts of material rendering the C analysis microinvasive and henceforth opening the possibility to target paint layers themselves (12).
So far, the most conclusive criterion in the field of counterfeit detection is the scientific proof of material anachronisms.
The establishment of the earliest possible date of realization of a painting, called the , is based on the comparison of materials present in an artwork with information on their earliest date of discovery or production.
With the advent of accelerator mass spectrometry (AMS) (2, 3), the amount of carbon necessary for obtaining a radiocarbon date was significantly reduced from a few grams down to 1 milligram carbon (4).
Technical advances in general, and especially in the field of gas ion source AMS (5, 6), where mixtures of CO and He gas are introduced straight into the GIS-AMS, have reduced sample requirements to micrograms of material (7), thereby setting a new milestone.