In Gordon and Sweets technique, which is used as a toning agent?

• A. Gold chloride
• B. Silver nitrate
• C. Copper sulfate
• D. Zinc chloride

Answer: (A)

In this staining approach, the step that sharpens and stabilizes the image is toning after the silver impregnation. Gold chloride is used for this toning. The gold ions exchange with the deposited silver on the reticulin fibers, forming a gold-silver complex that yields a deep brown-black color and helps prevent fading. This gives a crisp, high-contrast network of reticulin fibers against the lighter background, which is the hallmark you’re looking for in Gordon and Sweets staining. The silver nitrate step is what deposits the silver, while copper sulfate or zinc chloride aren’t used as the toning agent in this method.