Zinc Sulfide: An Essential Inorganic Pigment - Cultural Heritage Science Open Source

Home » Products » Pigments Checkers » Pigments Checker – Modern and Contemporary Art – Pigments’ List » PW 7 – zinc sulfide

PW 7 – zinc sulfide

This page presents the Spectroscopic analysis of this pigment.
The pigment has been examined using XRF spectroscopy, Raman spectroscopy, FTIR spectroscopy, and Reflectance Spectroscopy. These complementary techniques provide valuable insights into the pigment’s composition and structure.
This page aims to show which analytical methods are most effective for identifying this pigment in artworks and historical materials. By comparing results across different techniques, it serves as a practical reference for Heritage Science, Conservation, and Pigment Analysis.

Together with barium sulfate, it makes lithopone

Manufacturer/ product code: Kremer / 46350
Chemical Description: zinc sulfide
Color: white
Color Index: PW 7
Date: 1852

PW 7 – Zinc Sulfide is an inorganic white pigment composed of zinc sulfide (ZnS). Known for its soft, slightly warm white tone, PW 7 has historically been used as a pigment in paints, coatings, and plastics, as well as in optical and luminescent applications due to its unique physical properties. Unlike more opaque whites such as titanium or zinc oxide, zinc sulfide is moderately transparent, making it valuable for subtle tints and special effects.

Chemically, ZnS is stable under normal atmospheric conditions, with good resistance to light and heat. It is insoluble in water and most solvents, although it can slowly oxidize to zinc sulfate under prolonged exposure to moisture and oxygen. Its thermal stability and inertness make it suitable for incorporation into industrial paints, varnishes, plastics, and artistic media such as oil or tempera paints.

In practical use, PW 7 exhibits moderate opacity and low to moderate tinting strength, making it suitable as a softening agent in mixtures with other pigments or for creating subtle pastel shades. Its transparency allows for layering effects and smooth transitions in paints. Historically, it has been employed in decorative and artistic materials where a gentle white or a slightly translucent effect was desired.

From a conservation perspective, zinc sulfide is relatively inert and does not readily react with other pigments or binders under normal conditions, although it may darken slightly upon prolonged oxidation.