Iron chromate (FeCr₂O₄)
Iron chromate is a ceramic compound that is mainly used in glazes and engobes to generate a wide range of colors, which can vary from vibrant greens to dark browns, depending on several factors, such as firing conditions and the concentration of the material in the mixture. This pigment is especially prized in high-temperature ceramics, and is frequently used in the manufacture of stoneware and porcelain ware due to its ability to maintain color stability and quality at high temperatures.
It is known for its ability to change color according to kiln conditions, which gives it great versatility. In reducing atmospheres, where oxygen is limited, iron chromate tends to produce darker, metallic and deeper colors, which can include shades of brown and black. On the other hand, in oxidizing atmospheres, where oxygen is present in abundance, the colors tend to be softer, creating lighter, more vibrant ranges of greens and browns. Iron chromate is not only appreciated for its ability to modify colors, but also for its durability and resistance to extreme kiln conditions, making it an interesting component for high quality ceramic glazes.Interesting Fact
In some historical cultures, such as in Chinese ceramics, it was used to create vibrant green glazes that mimicked the appearance of precious stones, such as jade. This pigment, combined with advanced glazing techniques, was prized in the manufacture of bowls, vases and decorative plates.Helpful Tip
Use iron chromate in small amounts to prevent the glaze from becoming too dark or metallic. Test under different firing conditions to obtain the exact shade you desire, as results can vary significantly.
