I obtained this neat Limes Denarius of a young Caracalla with a very interesting reverse type of Athena. It was heavily rusted with simple iron oxide. Knowing that these sort of deposits often betray degraded surfaces underneath, I opted for a gentler sodium thiosulfate treatment instead of my standard sodium hydroxide soak. The iron was rather stubborn, and took quite a while to remove. In fact, the coin soaked in a very saturated solution of NaSO for over a combined 100 hours! However, since thiosulfate tends to be rather gentle(r) to coin surfaces, (it tends not to remove any details and tends not to etch the surface too destructively, retaining most of the original coin texture) I opted for this method instead of a quicker, but potentially more destructive strong acid or base treatment. After 100 hours, all the rust was gone, but the surfaces were a bit lackluster by virtue of the chemical. Fortunately. no details were degraded and the surface texture stayed relatively the same, albeit with a color change. Knowing that this was nothing that Ren Wax couldn't fix, I slopped some on, buffed it out, and resulved in a very attractive and rare(!) Secvritas Perpetva reverse type, RIC 330. I think this is a great improvement. Rust is technically mechnically removable, but I wasn't about to waste man-hours and eye strain attempting that. La Chemie pulls through as always. I would have preferred the original surface and color, but that simply would not have been possible in my opinion to retain the surface. I especially like the rather unusual spelling out of PONTIF (M AVR ANTON CAES PONTIF) instead of the typical PONT, PON, or P. Please show off your young Caracalla limes!
Good job. I have never used Ren Wax and I am not sure if it is available in my area, but in this case it clearly highlighted what's needed.
