Formulary's Nelson Gold Toner is similar to Kodak T-21 and is unmatched in its versatility. Tones range form just a hint of warmth to rich sepia browns. Toning can be stopped at any time between 5 and 20 minutes. Final images are permanent and are formed by a combination of silver sulfide and gold. The toner keeps almost indefinitely and its capacity is extended by adding small amounts of gold chloride solution, which is included in the kit. The toner is relatively inexpensive per print. One liter of solution is used to tone about 300 to 400 8x10" prints (with replenishment), depending upon tones desired. The satisfying results of this toner have made it a popular toner over the years. The chemicals in this kit are used to prepare a working solution, and the kit contains sufficient gold chloride from a replenisher solution.
Posted by Eric Searing on 11th Jan 2018
First mixing this toner is not something done in a hurry and it improves as it sits for a few days. Second, the toner is used at 100-110 degrees per the instructions. You can start the toner at 110 degrees and let it fall to the 90s and it still works. Placing your paper in hot water once in a while seems to help too. The fully developed images I tested with (on Ilford MGFB WT) lost some density in highlights and midtones but the brown tone achieved at 20 minutes is quite rich and open. The brown is very similar to Thiourea when mixed with a higher proportion of activator. The toner is slow working and in my tests did not change color tone in the highlights until 10 minutes, but I was not maintaining a consistent temperature. The long development time allows for pulling at the desired level of toning. It does dry down slightly warmer/browner. Following with Selenium also seems to darken toned areas slightly more. This toner is not that expensive per print and its long shelf life makes ideal for the infrequent printer. Give it a try if you like warm highlights to brown images. It is easier to control than the bleach+tone process.