Yellow ochre

About the chemical structure:

Chemical name:	Iron oxyhydroxide
Formula:	FeO(OH))
Refractive index:	n/a

Color:

Color Index (C.I.)	PY 43
155

How can you identify Yellow ochre?

Imaging:

UVF: no

IRFC: blue

OM: at high magnification, tiny crystals and crystalline clusters appear.

Analytics:

It's identified by means of FTIR and Raman.

Raman spectra: University College London;

FTIR spectra: IRUG

Usage and handling:

Permanence:	Toxicity:
Lightfast: eccellent. Degradation processes: stable. The pigment has good hiding power and excellent permanence in all media.	non toxic. Ocher is not considered toxic, but care should be used in handling the dry powder pigment to avoid inhaling the dust MSDS: Natural pigments

Literature:

Artists’ Pigments. A Handbook of Their History and Characteristics, Vol. 1, L. Feller, Ed., Cambridge University Press, London 1986, p. 37-46