How Cadmium yellow/red is made:
| Origin: artificial | Minerals: greenockite and hawleyite (at Mineralogy Database). Those natural minerals though known in nature were not used for pigments. |
 greenockite (CdS) |
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| Artificial variety of pigment | Precipitation of a solution of cadmium(II)-nitrate with a solution of sodium sulfide. |
| In the lab | |
| Materials needed: | Cadmium(II)-nitrate (Cd(NO3)2 · 4 H2O), Sodium sulfide (Na2S · 9 H2O) |
| Safety (MSDSs): | Cadmium(II)-nitrate, Sodium sulfide (at Fisher Scientific) |
| Method: | Solution of 9,7 g Cd(NO3)2 · 4 H2O in 50 ml deionized water is added slowly to a stirred solution of 8,3 g Na2S · 9 H2O in 50 ml deionized water. The resulting precipitate is filtered, dried and homogenized in a mortar. |
Illustration of the process:
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The ground pigment:
Pile of ground Cadmium yellow/red
Sections: