The following Le Noeud Papillon blog shows some Chestnut RM Williams that have been polished using Saphir Cognac. A closer match would have been the Saphir in the medium brown, however, you can see that by adding the cognac, the leather tone has changed only slightly. The results are pretty stunning and it really depends on what look you want to achieve with the polish.

Alternatively, we offer the Saphir Colour Chart and will happily order any colour from the Beaute du Cuir range.

I normally recommend the following 3 colours for the RM Williams in Chestnut depending on the look you want to achieve (lighter = brighter, darker = depth).

03 Light Brown - yellowish tones, will brighten up the shoe

10 Cognac - subtle yellow and chestnut tones, a mix between the light and medium brown

37 Medium Brown - very neutral medium brown

 

This shoe has been polished with medium brown. 

(Reno'Mat and Renovateur used prior to polish application)

 

The one below was polished with cognac. You can see this one is brighter and the yellow tones.

(Reno'Mat and Renovateur used prior to polish application)