Understanding the Causes of Fading in Black Granite: A Closer Look at Dyeing and Dye Removal

By Frederick M. Hueston, Stoneforensics.com

In recent times, concerns about fading black granite countertops have become increasingly common. This phenomenon primarily affects varieties like Absolute Black, Black Galaxy, Zimbabwe Black, and a few others. While some may attribute the fading to the misuse of cleaning chemicals and acids, it’s essential to recognize that the root cause of this issue often lies in the way these stones are treated and enhanced. In this article, we delve into the intricacies of why black granite may fade, focusing on the role of dyes and oils applied to the surface and their subsequent removal.The Misconceptions about Fading:

At first glance, it might appear that the fading of black granite is solely a result of incorrect cleaning practices, such as using inappropriate chemicals. While it is indeed crucial to treat granite surfaces with care and avoid abrasive substances, the increase in black granite fading can be attributed to more fundamental factors.

The Role of Dyes and Oils:

The fundamental reason behind fading black granite lies in the fact that some black granite, particularly those imported from Asia and India, are subjected to color enhancement through the application of dyes and oils. These dyes can take various forms, ranging from homemade blends like charcoal and linseed oil to pre-packaged color enhancers designed to darken the stone. The fading that users observe is, in reality, the gradual removal of these dyes and oils from the surface.

Testing for Dyed Granite:

Before purchasing a black granite slab, it is advisable to conduct a simple test to determine whether the stone has been treated with dyes. Here’s how to perform the test:

Take a clean white cloth or rag and apply a small amount of acetone to the surface of the granite.

Observe if any residue or black color transfers to the cloth. If it does, it’s an indication that the stone has been dyed.

If acetone yields no color transfer, try a different part of the slab with Methyl Ethyl Ketone (MEK).

If MEK causes any color to transfer, it confirms that the stone has been dyed.

These chemicals, acetone and MEK, can typically be found in most home improvement or paint supply stores.

The Unfortunate Truth about Dyed Granite:

The primary reason for dyeing black granite is that its natural color tends to be gray and may lack the deep, pitch-black hue that some black granites are known for. To address this, unscrupulous individuals in the industry resort to deceptive methods to enhance the stone’s appearance and sell it as genuine black granite. Unfortunately, there is no effective solution to reverse the fading caused by the removal of dyes and oils. The only remedy, in such cases, is to reapply the dye to the granite surface.

Additional Consideration: Resin Injection

In addition to dyes and oils, it is worth noting that some types of black granite are also injected with resins during the manufacturing process. These resins can contribute to darkening the granite’s appearance, and they should be considered alongside the role of dyes in color enhancement.

The fading of black granite is a complex issue that often originates from the treatment of these stones with dyes and oils to achieve the desired deep black color. To avoid disappointment, it’s crucial for consumers to be aware of these practices and perform the acetone or MEK test before making a purchase. Once fading has occurred, there is no effective restoration method other than reapplying the dye. By understanding the intricacies of the treatment processes involved in black granite, consumers and industry professionals can make informed decisions and appreciate the true nature of these stunning stones.