Quadrantal correctors are made of soft iron and, as such, do not polish up too well. They are usually painted black, although I've seen them painted red and green in an attempt to achieve a "yachty" look. Always wondered about the capabilities of those who did that; perhaps they should carry it further and paint the port side deck red and starboard green to keep themselves straight! Polishing spheres in general takes an experienced touch; one not found in the average ordinary seaman. Most deep sea crews find the job onerous and prefer some type of shore gang to be employed. While expensive, these laborers can be found in most deep water ports but do display a wide range of proficiency. As in most areas maritime, if you find an individual with the requisite skill, and the work ethic to acheive a superb outcome, it is best to always employ that same individual. For years Olongapo city was renowned for this trade and many experienced seamen would have their sphere work done nowhere else. Weather and cargo requirements sometimes required employing others will less skill, although the results were, surprisingly, much the same. When spheres acheive a brass, or brass-like state, it has been found that a vigorous rubbing by virtually anyone at hand is sufficient to polish them enough until the job can be done properly by a competent professional.