Zinc sulfide (ZnS) can be white or yellow depending on its purity and crystal structure.

* Pure zinc sulfide is white.

* Impurities can cause the color to shift towards yellow.

* The crystal structure also plays a role. For example, the cubic form (sphalerite) is typically white, while the hexagonal form (wurtzite) can be slightly yellow.

So, while white is the most common color, it can be found in different shades of white and yellow depending on its properties.