There appears to be a lot of confusion when it comes to "chrome" on Redbones. White will crop up occasionally in almost any Redbone line. (White on the chest and/or feet can appear in other dog breeds as well--Dobermans immediately come to mind.) Even some of the country's top Redbone show dogs have some white. Some pups are born solid while a littermate or two might have a white patch. A white patch will often fade away until no white remains at all, just like some dark muzzles on pups fade away to a uniform red color. As adults, you would never know the odd color was ever there. However, some dogs retain the white from birth to adulthood and it stays that way throughout their lives.
The shots below show one of our pups at less than a week old and again at 7 months old. No white remains.