Marc-
Elting’s Napoleonic Uniforms Vol.III has quite a few Knotel plates on the Neapolitan army of Murat, including a grenadier like yours…in fact it has more plates than their military importance would warrant, but Murat’s army has been described as one of the “prettiest” armies that ever existed. Murat loved the color Amaranth, and a good many of his units had this as a facing color; this looks like the color in your link (or Rose?). I painted Pegaso’s Neapolitan Hussar awhile back and painted Amaranth, which is kind of a dark crimson. Besides the more dominant Amaranth, some of the other Infantry Regiments had facings in Orange, Scarlet, Rose, and Crimson as well.
FYI, the 5th, 6th and 7th Regiments mentioned in the link above in 1812 had white uniforms with facings of Green, Orange, and Yellow, respectively. The 6th had Rose or "light Crimson" facings in 1811, but this changed to Orange before the Russian Campaign.
Amaranth is described as “a deep reddish purple to dark or grayish, purplish red” or “a dark red to purple azo dye”. Vallejo and others have this in their paint ranges, and I don’t recall exactly how I mixed this in oils but I wouldn’t be surprised if I used Purple Madder Alizarin as a base mixed with Cadmium Red with flesh/pink highlights. Hope this helps.
