Here’s one of some unusual grinding bits we found. Length 3”, solid shank dia. 5/8”. The stone looks like some we have that are supposed to be diamond-impregnated. What would be a typical use for these? I thought maybe jig grinder but I don’t know if jig grinder chucks hold anything that big, typical jig grinder stones I’ve seen had 1/4’ shanks. So, what rpm limit, what application?