I have a very small sample to go by, and mine is Uruguyan...My trigger guard is brass. Mine was converted to a smokeless cartridge for Uruguay in 1894. It is all blued. Since I have had this (couple years) I have been researching all I can find about it. Some I have seen are "In the white", some are blued like mine.
You can search on Gunbroker, and look at others... There are videos on the "Dovitiis" Mausers.
Sorry I am not more help.