Analysis of Cima PaintingOpt

Analysis of Cima PaintingOpt - Gesso Underpaint LMA on the...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
Investigating Cima In 1504 Cima da Conegliano finished an altarpiece “the Incredulity of St Thomas”. After suffering damage it was bought by the National Gallery in 1861 but in 1969 it required major restoration. To help with the restoration tests were carried out: 100’s of free ppt’s from www.pptpoint.com library
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Painting
Background image of page 2
Reflectance Spectra A B Use your data sheet to identify the pigments used in each area. What are the chemical substances What colour would you expect each to appear ? 400 450 500 550 600 650 700 750 0 50 400 450 500 550 600 650 700 750 0 10 20 30 40 50 60 Wavelength /nm % reflection
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Does this help ?
Background image of page 4
Position of samples A and B
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Now look at St Peter's Mantle
Background image of page 6
L aser M icrospectral A nalysis Laser light Electrodes Spectrometer Paint Sample
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
A fragment of paint was cross sectioned
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 10
Background image of page 11
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Gesso Underpaint LMA on the upper layer gave lines at 228.8 nm and 235.0 nm . Identify the element present and hence the pigments used. Identification of oils (1) A sample of paint is hydrolysed to give the potassium salts of the saturated fatty acids OH OH OH O O O O O O O O O O O O K + K + K + KOH(aq) + Identification of oils (2) The potassium salts are converted to the free acids. And then to the methyl esters. O O K + O OH H Cl O OH O O CH 3 CH 2 N 2 So what medium did Cima use ? glc shows the proportions of saturated esters. What happened to the unsaturated acids ? For Cima's painting palmitate/stearate = 76/54 = 1.4 What medium has this ratio ?...
View Full Document

This note was uploaded on 11/09/2011 for the course CHEM 210 taught by Professor Wilson during the Fall '10 term at BYU.

Page1 / 11

Analysis of Cima PaintingOpt - Gesso Underpaint LMA on the...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online