Madder lake

/   /

font size:  a  a  a

About the chemical structure:

Chemical name: Alizarin (1,2-dihydroxyanthraquinone),
Purpurin (1,2,4-trihydroxyanthraquinone)
Formula:

C14H8O4, C14H8O5

3D model:

grey = carbon, red = oxygen, white = hydrogen

Refractive index: Madder lake: 1.66; alizarin: 1.70

Color:

Color Index (C.I.) NR 9

How can you identify Madder lake ?

Imaging:

UVF: no

IRFC: orange

Beccafumi, 1486-1551, Tuscany, Italy

The red gown of the Virgin sohws up in orange, being painted with madder lake.

 

OM: The base on which both varieties are substrated is indistinguishable under the microscope. Nor can the natural and artificial be identified even at high magnification.

Microscopic appearance at x500 mag

Analytics:

It's identified by means of FTIR.

 

FTIR spectra: IRUG

 

 

 

Usage and handling:

Permanence: Toxicity:

Lightfast: excellent

Degradation processes: One of the most stable organic pigments/dye stuffs.

non toxic. The essential coloring matter of the madder root is considered to be non-toxic.

MSDS: Kremer

Literature:

Artists’ Pigments. A Handbook of Their History and Characteristics, Vol 3: E.W. Fitzhugh (Ed.) Oxford University Press 1997, p. 109 - 142.

Stössel, I., Rote Farblacke in der Malerei - Herstellung und Verwendung im deutschsprachigen Raum zwischen ca. 1400-1850, Publikationsreihe des Instituts für Malerei Stuttgart, 1985

Koch, H. M. und Pfeifer, P., Naturfarbstoffe im Unterricht. Antrachinonfarbstoffe der Krappwurzel. Praxis der Naturw.-Chemie, 10, 1999, s. 25-29

 Sections:  

  purples  

  blues  

  greens  

  yellows  

  oranges  

  reds  

  whites  

  browns  

  blacks