I had an aluminum platter and used Wenol Metal Polish (Purchased through Amazon. You can also read the reviews). My mother has used this on metals for years. The results produced a high luster.
Agree with Stringreen, check with VPI is there is a coating on the aluminum. Otherwise, give the Wenol a try on the underside of the platter, first.
Agree with Stringreen, check with VPI is there is a coating on the aluminum. Otherwise, give the Wenol a try on the underside of the platter, first.